Basic Science - Class 8 General Knowledge - Extra Questions

Why do water pipes, in hilly areas, often burst on a cold frosty night?



What is a 'formula' in Chemistry?



Why is a small space left between each set of two rails of a railway line?



How are positive and negative charges produced during a thunderstorm?



Why does not moon have an atmosphere?



Are the lead pencils made of lead?



Why is Miner's Safety Lamp a safe lamp?



The process of electric _______ between clouds and the earth or between different clouds causes _______.



Why is a person in a moving vehicle thrown forward when the vehicle stops suddenly?



Describe the achievements of Horticulture Development Programme.



Why does milk turn sour?



Why is it easier to roll a barrel than to pull it along the road?



What is the temperature $$32$$ degrees Fahrenheit in degree Celsius?



Is chemistry a physical science?



Why is Organic chemistry important? What are the applications of this branch of chemistry? Who uses it? How is it used?



How is electric discharge fatal for human beings?



Why does Earth have day and night?



If it is noon at one location on Earth, what time is it at a location directly on the other side of Earth?



Where is the Moon in its orbit at the time of solar eclipse?



The footprints on the moon were made in the early 1970 s. How do the footprints, you think look today and why?
285013_a76283f066bc474bb74ca720ee230521.png



Match column-I with column-II and select the correct answer using the codes given below:



When the Moon is full, where is it in its orbit around Earth?



Why is the path of water curved on coming out of horizontal jet?



CONCEPTUAL QUESTIONS 
Are there more nanoseconds in a second than the number of seconds in a year?



What is ecosystem? Write briefly about its components and their interdependence.



A drop of water or mercury on a clean glass plate is circular in shape. Why?



When a moving train slows down quickly, will a passenger tend to fall backward or forward. Explain why?



x and y displacements of a particle are given as x(t) = a $$sin \omega t$$ and y(t) = a $$sin 2\omega t$$. Its trajectory will look like :



An object is placed at a distance of 10 cm from a concave mirror of focal length 20 cm.
a) Draw ray diagram for the formation of image 
b) Calculate the image distance
c) state 2 characteristics of the image formed.



A particle is moving along a circular path of radius $$R$$ in such a way that at any instant magnitude of radial acceleration & tangential acceleration are equal. If at $$t=0$$ velocity of particle is $$v_{0}$$, then find the time period of first revolution of the particle .



A uniform solid sphere of radius $$R$$, rolling without sliding on a horizontal surface with an angular velocity $$\omega_{0}$$, meets a rough inclined plane of inclination $$\theta = 60^{\circ}$$. The sphere starts pure rolling up the plane with an angular velocity $$\omega$$. Find the value of $$\omega$$.
1212796_a4ba58e6138f463e82a2d6a5761bfc69.png



Two towns A and B are connected by a regular bus service with a bus leaving in either direction every T minutes.A man cycling with a speed of  20 $$km\;{h^{ - 1}}$$ in  the direction A to B notices that a bus goes  past him every 18 min in the direction of  his motion.and every 6 min in the opposite direction .What is the period T of the bus service and with what speed (assumed constant) do the  buses ply on the road?



What is chemistry?



What is the difference between distance and displacement?



What is the $$S.I$$ unit of electric potential?



Why force is a vector quantity?



What does it mean for a species to be in stasis?



Why is acceleration measured in meters / seconds squared?



Which is warmer -30C or -30 F?



Why are peroxisomes important in cells?



Why is the number of protons and electrons equal in an atom?



Why is meiosis not a part of the cell cycle?



Why are standard units of measurement important to scientists?



Why is impulse a vector?



Why do the phospholipids surrounding the cell form a bilayer?



Why is the atomic model useful?



Why are SI units helpful?



Whats $$  45 $$ degrees F. in celcius?



What quantum numbers refer to a 4d orbital?



What scientists study the history of life on earth?



When the pressure on a gas increases, will the volume increase or decrease?



What is the strongest of the four fundamental forces?



What $$SI$$ units are used to measure power?



Which has the larger atomic radius:  $$ Cl - $$ or $$K + $$ ? 



What is the study of cells called?



What property of an object determines how much inertia it has?



What property is unique to stem cells?



What is thermochemistry?



What is the percentage by mass of ammonium nitrate?



What is the percentage composition of N, H and O in ammonium nitrate,$$ NH_4NO_3 $$?



What is the pressure conversion factor for torr to kpa?



What is the main component of the cell membrane? Why is the main component?



What is the SI unit of mass ?



What is the weight in lbs of a 75-kg person?



What is the relationship between pressure and volume ?



What kind of organism has pseudopods?



What is time?



What is the number of significant figures in each of the following?
$$ 10.0005 g $$
$$ 0.003423 mm $$
$$ 2900 +100 ft $$
$$ 8.9 \times 10^5 L $$



What is the nucleon number?



What is the number of neutrons in $$$^{10}_5 B $$ ?



What is the mass of $$HCl$$ in a $$500\ mL$$ sample of $$6.0\ M\ HCl$$?



What is the isotope symbol for an atom that contain $$82$$ protons and $$125$$ neutrons?



What is the number of moles in $$ 36 g $$ of $$ H_2O $$?



What is instantaneous rate of change formula?



What is the number of protons in an atom of carbon-12?



What is the mass of $$Cl$$ in $$21\ g$$ of $$NaCl$$?



What is the percent by mass of oxygen in $$ Mg (NO_3)_2 $$?



What is the difference between organism, population, community, ecosystem, biome and biosphere ?



What is the conversions of grams to mL?



What is the conversion factor between km/hr and m/s?



What is the difference between a therapist, psychologist, psychiatrist, and a counselor?



What is the difference between Astrophysics and Cosmology?



What is the basic SI unit of density?



What is the angular momentum of earth?



What is the Fahrenheit equivalent of $$ 15 $$ degrees Celsius?



What is the Bronsted-Lowry acid and base versus Lewis?



What is the amount of space occupied by a substance?



What is species richness?



What is $$75$$ degrees fahrenheit converted into celsius and kelvin ?



What is electronegativity?



What is $$22$$ degrees in Fahrenheit in Celsius?



What is electronegativity a measure of ?



What is a particle that moves around the outside of the nucleus?



What is a neutral atom?



What is $${200}^{o}F$$ in celsius?



What is formula for converting Farenheight to Celsius?



What is $$64$$ ounces in pounds ?



What instrument measures wind speed near the earth's surface?



What is $$80$$ degrees Celsius in Fahrenheit?



What is linear mass density?



What is $$120$$ degrees Fahrenheit in celsius?



What is $$19C$$ in Farehneit?



What is $${19}^{o}F$$ in celsius?



What are the branches of chemistry and their definition ?



What is $$90^{0}F$$ in celsius?



What is $$20$$ degrees celsius in Fahrenheit?



What is $$42$$ degrees celsius in fahrenheit ?



The maximum default speed limit on the Autobahn in Germany is 100 km/hr. What is this speed in mi/hr?



Is density a physical or chemical property?



What does temperature measure?



There are $$8$$ ounces in a $$h$$ pound. How many ounces are in $$7\frac{3}{4}$$ lbs?



Is density temperature-dependent?



What are some examples of quantitative and qualitative measurements ?



There are $$5$$ miles to $$8 km$$. How many $$km$$ in $$80$$ miles?



What is anything that has mass and occupies space?



The temperature $$212 F$$ is the same as what in degrees $$C$$?



What is density?



How many arcseconds are in one arcminute?



How many arcseconds are in degree?



How many gallons is $$2$$ litres?



How many feet is in $$3$$ miles?



How many $$1/3$$ cups do you need to make $$1/2$$ cup?



How many feet per second is $$23$$ joules a sec?



How many kilometers is $$1.7\ miles?$$



How many fluid oz. are in a gallon?



How many arcseconds are in $$1^o$$?



How many feet is in $$15$$ miles?



How many feet are in $$2.4$$  miles?



How many feet are in $$4$$ miles? 



How many feet are in $$1000$$ yards? 



How many inches is in $$1$$ yard?



How many inches is in $$5$$ yards?



How many inches is there in $$1/8th$$ of a yard?



How many feet is in a mile?



How long is an eon in years?



How many feet are in a football field that is $$100$$ yards?



How long is $$7/10$$ of a mile, in feet?



How many degrees celsius equals one degree Fahrenheit?



How many grams are in $$2000 mg$$?



How many feet are in $$1/2$$ of a mile?



How many feet are in $$1$$ yard?



How many cups are in two gallons?



How many cups are there in nine ounces?



How many degrees Celsius is $$67\ F$$?



How long is $$33$$ inches added to $$4$$ feet $$7$$ inches?



How long in meters is $$670$$ nanometers?



How many cups are in a quart?



The official length for a marathon race is $$26.2$$ miles. How many yards long is a marathon? How many feet?



How many cups are in a gallon?



What is an equilibrant?



The outside air temperature is $$30^{0}F$$, what is the temperature in Kelvin?



How many cups are equivalent to one pint?



How does mass affect density ? How does volume affect density ?



The ratio of two people's weight remains the same, whether measured in pounds or kilograms? $$( 1kg = 2.2lb )$$



How many cups are in $$20$$ quarts?



How many cups are in $$1/2$$ a gallon?



Is it possible to add a scalar to a vector? Why or why not?



How does chemistry relate to biology ?



The freezing point of an aqueous sodium chloride solution is -0.20C. What is the molality of the solution?



How would you convert $$\dfrac {g}{cm^{3}}$$ to $$mL$$?



How do you solve for $$f$$ in $$C=\dfrac{5}{9}(f-32)$$?



How does a conversion factor differ from a measurement ?



How much is $$90$$ C in Fahrenheit?



How does a hypothesis becomes a theory ?



How to convert L to dm3 and ml to cm3 Questions: 1) $$10cm3$$ to Gm? 2) $$10L$$ to Gm? 3) $$10mL$$ to Gm? 4) $$10dm3$$ to Gm?



How to convert $$2.5$$ radian to degree/minute/second?



How to convert rev/s into rad/sec?



How much is $$23$$-kg in pounds?



The atomic weight of aluminum is 26.982 u, how many aluminum atoms are there in a 4.55g sample of aluminum?



How much is $$70$$ degrees Fahrenheit in Celsius?



How much is $$10$$ kg in pounds?



Reaction: 
$$\mathrm{Mg}+2 \mathrm{HCl} \rightarrow \mathrm{MgCl}_{2}+\mathrm{H}_{2}$$ 

What volume of hydrogen  is produced from the reaction of 50.0 g of Mg and the equivalent of 75.0 g of HCl?



What is an activated complex?



How can you calculate mass if density and volume are known ?



How much is $$63$$ kg in pounds?



Specific gravity of HCl is 1.What is its Molarity of such solution containg 17 gm of HCl?



How do you find volume when given mass?



In what units is wind speed measured?



How do you convert seconds to days ?



Why is a $$1\,dm^{3}$$ volume equivalent to $$1\,L$$ ?



$$32$$ gallons is how many pints?



$$3 km/h= m/s$$?



Which one is greater 5000cm. or 5 meters?



How are protons, neutrons, and electrons similar?



When calculating percent error, what does it mean if I get a negative number for mass?



How many  $$1cm^3$$ in a $$10m^2$$ volume?



What is the scientific name for Gold?



$$3/4$$ lbs is equal to how many ounces?



As sample size increases, what happens to the standard error of M?



$$10$$ yards is how many inches?



What functional groups are found in proteins?



$$100$$ yards is equal to how may feet?



$$2$$ pounds equals how many ounces?



$$25 mm$$ is equal to how many $$cm$$?



Introduction to vectors
Why are vectors important in physics?



$$100$$ kilometers is equal to how many miles?



Is density an intensive or extensive property ?



Curium has a half life of $$1.5$$ horse, how much of a $$1000g$$ sample remains after : $$1.5$$ hrs? $$3$$ hrs? $$4.5$$ hrs? $$6$$ hrs?



Derive the formula for Celsius to Fahrenheit?



Can displacement be negative?



How do you convert $$36$$ cm/sec to mph ?



$$1/4 lb$$ is how many ounces?



Can matter be destroyed?



Angular speed of hour hand of a clock in degree per second ?



$$1\frac{3}{4}$$ hours equals how many minutes?



$$1 cm$$ equals how many meters?



$$1 kg$$ is equal to how many pounds?



How force is a vector quantity ?



If Earth has a mass of $$5.972 * 10^{24} kg$$ and Mars has a mass of $$6.39 * 10^{23} kg$$, and the distance between them is $$225 * 10^6 m$$, with what force does Earth pull on Mars?



If the speed of light is $$3×10^8$$, determine the distance it takes in $$1$$ light year. Report your results in $$km$$ and in $$m$$.



Convert $$18\ km/h$$ to $$m/s$$? Answers with steps



What is the $$SI$$ unit of acceleration?



Why is angular momentum perpendicular ?



Can average rate of change be negative?



What is $$0.25$$ kilometers expressed in centimeters?



Can a rate of change be negative?



Convert $$22\ m/s^{2}$$ to $$km/m^{2}$$?



How many significant figures are in the measurement $$0.020\ km $$ ?



How many microliters are in $$41.0\ mL $$ ?



What is the difference uniform and constant velocity ?Is acceleration zero in case of both constant and uniform velocity?



The density of a sample of aluminum is $$2.70 g/cm^3$$. You submerse a sample of aluminum in water, and the volume of the water rises $$1.3 L$$ ($$1.3 L$$ is displaced by the aluminum). Using the correct number of significant figures, what is the mass of the sample?



What values of $$m_l$$ are permitted for an electron with $$l=3$$ ?



Which Lewis electron-dot diagram is correct for a $$ S^{2 -}$$ ion ?



Explain why displacement is a vector quantity?



State the CGS and SI unit of surface tension.



A heavy of mass m hangs between two fixed points A and B at an angle 0 with the horizontal as shown in the figure . What is the tension at the lowest point in the string .



A bob of mass $$m$$ is suspended by a light string of length $$L$$. It it imparted a horizontal velocity $${v}_{0}$$ at the lowest point $$A$$ such that it completes a semi-circular trajectory in the vertical pane with the string becoming slack only on reaching the topmost point $$C$$. Obtain an expression for (i) $${v}_{a}$$; (ii) the speeds at points $$B$$ and $$C$$ (iii) the ratio of the kinetic energies $$({K}_{B}/{K}_{C})$$ at $$B$$ and $$C$$. Comment on the nature of the trajectory of the bob after it reaches the point $$C$$.



A sample of sulfur hexafluoride gas occupies $$8.62 \,L$$ at 221 degrees Celsius. Assuming that the pressure remains constant, what temperature (in Celsius) is needed to reduce the volume to $$2.61\, L$$?



A body of mass gm is attached to a spring constant k = 100 N/m and it is performing  damped oscilliations . If damping constant is 0 .2 and driving force is F   = F (ot) , where F  =  20 N . Find the amplitude of oscillation at resonance 



What is the temperature $$-34^oC$$ expressed in Kelvin?



The Mohs scale is a measure of what of a mineral?



State Kepler's law of motion :



A particle is thrown from the top of a building of height $$50\ m$$ with a velocity $$30\ m/s$$ at an angle of $$30^{th}$$ above the horizontal then the distance from the base building to the point where the particle hits the ground is



Express for time period of a simple pendulum by dimensional analysis.



Define angular velocity. Show that the centripetal force on a particle undergoing uniform circular motion is $$- m\omega^2 \overrightarrow{r}$$.



$$10$$ divisions of vernier scale.



Obtain the dimension of power and force.



In a boat race on still water the speed of one boat is to that of another is $$4 : 7$$. When the number of rowers in each boat is increased by $$5$$. Their speeds are found to be as $$13:19$$. Assuming that the speed of each boat is proportional to numbers of rowers in it. Find the original number of rowers in each boat.



What are derived units ?



A particle is moving eastwards with a speed of 6m/s. After 6 s, the particle is found to be moving with same speed in a direction $$60^{\circ}$$ north of east. The magnitude of average acceleration in this interval of time is
1890817_789739158f564dc7b05fb115d6cc15ee.PNG



Block $$A$$ in the diagram below has a mass of $$1.81\ kg$$ and block $$B$$ has a mass of $$3.36\ kg$$. The coefficient static friction between all the surface is $$0.25$$ Blocks $$A$$ and $$B$$ are connected by a light flexible cord passing around a small frictionless pulley that is fastened to a wall. The cord will not stretch when it is pulled as its ends.
1890789_13ba1e626776457387aee67c725959b7.png



Figure (9-E11) shows a small block of mass m which is started with a speed v on the horizontal part of the bigger block of mass M placed on a horizontal floor. The curved part of the surface shown in semicircular. All the surfaces are frictionless. Find the speed of the bigger block when the smaller block reaches the point A of the surface.
1890901_90453b36a8464df88c5543e90f98ea57.PNG



The distance travelled by an object in time $$ (100 \pm 1) s $$ is $$(5.2\pm 0.1)m.$$ What is the speed and its error?



A beaker of radius $$15\ cm$$ is filled with a liquid of surface tension $$0.075\ N/m$$. Force across an imaginary diameter on the surface of the liquid is $$\dfrac 9x \times 10^{-2}N$$. Find $$x$$. 



A . bullet fired from a gun with a velocity of $$ 140ms^{-1} $$ strikes the ground at the same level as the gun at a distance of 1 km . Find the angle of inclination with the horizontal at which the bullet is fired .Take $$  g = 9.8ms^{-2} $$.



What is the magnitude of the gravitational force between the earth and a 1 kg object on its surface? (Mass of the earth is 6 × 1024 kg and radius of the earth is 6.4 × 106m.)



Two concentric shells of different masses $$m_1$$ and $$m_2$$ are having a sliding particle of mass $$m$$. The forces on the particle at positions $$I,II$$ and $$III$$ are respectively.

1899708_3c31a07430204df48306365e2f45b5d2.png



In the arrangement shown in figure, the mass of the body $$A$$ is $$n=4$$ times that of the body $$B$$. The height $$h=20cm$$. At a certain instant, the body $$B$$ is released and the system is set in motion. What is the maximum height (in cm) the body $$B$$ will go up? Assume enough space above $$B$$ and $$A$$ sticks to ground. ($$A$$ and $$B$$ are of small size) $$(g=10m/s^2)$$.

1899682_e380cc2bceca49ba8d54ab6482b44a5c.png



(a) A $$2Kg$$ block situated on a smooth fixed inclined is connected to a string of negligible mass, with spring constant $$k=100Nm^{-1}$$, via a friction-less pulley. The block is released from rest when the spring is unstretched. How far does the block move down the incline before coming (momentarily) to rest? What is its acceleration at its lowest point?
(b) The experiment is repeated on a rough incline. If the block is observed to move $$0.20m$$ down along the incline before it comes to instantaneous rest,calculate the coefficient of kinetic friction.

1899701_6ea3c3c695034ce18a7da5d34c7af44d.png



A wheel is rotating with angular velocity $$2rad/s$$. It is subjected to a uniform angular acceleration $$2.0rad/s^2$$
(a) What angular velocity does the wheel acquire after $$10s$$?
(b) How many revolutions will it make in this time interval?



A stone weighting $$0.5kg$$ tied to a rope of length $$0.5m$$ revolves along a circular path in a vertical plane. The tension of the rope at the bottom point of the circle is $$45$$ newton. To what height will the stone rise if the rope breaks at the moment when the velocity is directed upwards? $$(g=10m/s^)$$



A bomb explodes into three fragments of equal masses. The two fragments have linear momentum as $$-3p\hat{i}$$ and $$2p\hat{j}$$. What will be the magnitude of momentum of third fragment?



A flywheel of radius $$ 0.4m $$, mass $$ 10kg $$ Initially at rest  after one minute Increase its speed from $$ 0 $$ to $$ 300 rpm $$ then the torque on the flywheel is :-



Calculate the mass of $$ 2.5 $$ g atom oxygen.



A particle of mass 1 kg is moving on a circular path of radius 1 m. Its kinetic energy is $$ K = bt^{4}, $$ where $$ b = 1 J/s. $$ The force acting on the particle at $$ t = 1s $$ is $$ (2x)^{1/2} m/s^{2}.$$  Find the value of $$ x $$. 



The masses of two  bodies are measured to be $$ 15 . 7 \pm 0.2 kg $$ and $$ 27.3 \pm 0.3 $$ kg What is the total mass of the two and the error in it ?



A painter is raising himself and the crate on which he stands with an acceleration of $$5m/s^2$$ by a mass-less rope and pulley arrangement. Mass of the painter is $$100kg$$ and that of the crate is $$50kg$$. If $$g=10m/s^2$$, then the tension



State and explain Bohr's model with limitations.



A body of mass $$2\ kg$$ is lying on a rough inclined plane od inclination $$30^o$$. Find the magnitude of the force parallel to the incline needed to make the block move
Up the incline



A body of mass $$2\ kg$$ is lying on a rough inclined plane od inclination $$30^o$$. Find the magnitude of the force parallel to the incline needed to make the block move
Down incline.
Coefficient of static friction $$=0.2$$



Three forces of magnitude $$5N,12N$$ and $$13N$$ acting simultaneously on a particle to keep it in equilibrium. The angle between the force $$5N$$ and $$13N$$ is 



Three bodies of equal masses are placed at $$(0 , 0) , (a , 0) $$ and at $$ \left  (\dfrac{a}{2} , \dfrac{a \sqrt{3}}{2} \right  ) $$. 
Find out the coordinates of center of mass.



$$Wb/\Omega$$ unit is representing which physical quantity?



A small body of mass $$m$$ is located on a horizontal plane at the point $$O$$. The body acquires a horizontal velocity $$v_{0}$$. Find the mean power developed by the friction force during the whole time of motion, if the friction coefficient $$k = 0.27, m = 1.0\ kg$$, and $$v_{0} = 1.5\ m/s$$.



What is meant by unit of physical quantity.



 A  50 kg boy runs at a speed   of 10 m/s and  jumps onto a  cart as shown in the fig . The cart is initially at rest . If the speed of the cart  with the boy on it is 2.50  m /s , what is the mass of the cart  ?
1900840_738d902740ba44de8507636adbdc4f06.png



If a point is moving under uniform acceleration covers successive equal distance in time $$t_1, t_2$$ and $$t_3$$, then the correct relation between $$t_1, t_2$$ and $$t_3$$ is



What is unit vector? Explain it.



Two block of mass 4  kg and   6  kg an attach  in a vertical with the  help of  ideal strings . Find tension of  point  A   and B
1900847_881ccc5f9e694affb5b19dd9b0df8e1e.PNG



In the following fig $$ r_{1}$$ and $$r_{2} $$ are 10 cm  and 20 cm.respectively  . If the moment of inertia of the wheel a $$ 1500\ kg-m^{2} $$v , then determine  its angular acceleration  :-
1900885_d199f02e7f65475582cc23f474c08749.png



A  bullet is fired with speed 50 m /s at $$45^{o} $$ angle. Find the height of the bullet above the point of projection when its direction of motion makes angle $$ 30^{o} $$ with the horizontal



Determine the minimum coefficient of friction between a thin rod and a floor at which a person can slowly lift the rod from the floor , without slipping to the vertical position applying at its end a force always perpendicular to its length



Establish the relationship between related physical quantities using the dimensional analysis ?



A boy of mass 40 kg is hanging from the horizontal branch of a tree. The tension in his arms is minimum when the angle between the arms is:



On Celsius scale , the temperature of the body is increased by $$45^{\circ} C $$. The increase in temperature on Fahrenheit scale is 



Using dimension show that $$ 1 \;Jaule = 10^{2} erg $$



A block of mass $$100g$$ slides on a rough horizontal surface. If the speed of the block decreases from $$10ms^{-1}$$ to $$5ms^{-1}$$, find the thermal energy developed in the process.



In the figure shown, the acceleration of A is $$2\,m/s^2$$ to left and acceleration of B is $$1\,m/s^2$$ to left.
Find the magnitude of acceleration of C in $$,m/s^2$$
1901439_2729bdc3560448cb8121f9a8ea73f580.png



Find the value of T = ?
1901628_d4fc4e60df0b4f69a8cbbac6a446e6f1.png



What is the work done? 



What are scalar and vector quantities



What would be the position of the car B with respect to the car A at t = 0 ? ( assume that car B starts uniform motion from t = 0 )
1902224_47075039af9347e0b5ca276a2804e139.PNG



If the rod of the previous problem horizontal ( no banking ) what should be the minimum friction coefficient so that a scooter going at 18 km / hr does not skid ?



Find moment of inertia of a solid hemisphere of mass M shown in figure, about an axis AA' passing through its centre of mass.
1902070_5913f88424794bf18d2ed401a2fd60fd.PNG



Distance between the place $$A$$ and $$B$$ is $$225\ km$$. In a map this this distance is denoted by a segment of length $$2.5\ cm$$. In the same map if the distance of place $$C$$ from $$A$$ is $$4.2\ cm$$, then what is the actual distance between $$A$$ and $$C$$.



With what average velocity must the blood flow through an artery of radius $$2\times 10^{3} m$$ take place for the flow to be laminar? Find the flow rate. Viscosity of blood $$= 2.084\times 10^{-3} Pa\ s$$ and density of blood $$= 1.06\times 10^{3} kg/m^{3}. (0.98\ ms^{-1}; 1.23 \times 10^{-5} m^{3}s^{-1})$$.



On the normal chess board as shown $$I_{1}$$ & $$I_{2}$$ are two insects which starts moving towards each other. Each insect moving with the same constant speed.



The force between two electrons when placed in air is equal to $$0.5$$ times the weight of an electron. Find the distance between two electrons.



Find velocity if mass of particle is 0.1 kg. 
1902627_9b09b90a9eca48e08576750127bca6a3.png



What is the max vertical height to which a baseball player can through a ball is he can throw it to a max horizontal distance of $$100\ m$$?



When the wedge moves through a distance x, the speed of the rod is:
1902643_6d561b373086438986671509eff6a2dd.png



Prove $$x = x_0 + v_0t + \dfrac{1}{2}at^2$$



Where does the package strike the ground relative to the point directly below where it was released?



A truck starts from rest and rolls down a hill with constant acceleration. It travels a distance of $$400\ m$$ in $$20\ s$$. Calculate the acceleration and the force acting on it if its mass $$7$$ metric tonnes.



Derive the kinematic equation for uniformly accelerated motion by using of the analytical method of $$v-t$$ graph.



Define Mole fraction and Molarity.



The magnitude and direction and section of velocities of two identical frictional  as before they strike  each them are as shown . Assuming e = 0.9 determine the magnitude of each after the impact .
1903670_9aecc08539064fe2805d37d75496b456.PNG



A particle A of mass 2 m  is held  on a smooth horizontal  table and is attached to one end of an inefastic  string which runs over a smooth light pulley at the edge of the table. At the end of the string there hangs another particle  B of mass m ,The distance from A to pulley is 1 . The particle A  is then projected  towards  the pulley with velocity  u .
The common velocity  when A reaches the pulley (assume that B has not yet reached the ground )
1903701_ed7a04acf62b419c97b3f770aa440bb1.PNG



What is absolute error, mean absolute error and relative error?



How do you convert grams to moles and moles to grams?



815 gal/h is equivalent to how many qt/sec?



A body travelling along a straight line traversed one third of the total distance with a velocity $$ 4 ms ^{-1} $$ . The remaining part of the distance was covered with a velocity $$ 2ms^{-1} $$ for the other half of time . What is the mean velocity average over the whole time of motion ? 



A test charge q  is  moved without acceleration  from A  to C along the path  from A  to B and  then d=from B to C in electric field E as shown in the fig 
Calculate the potential difference between A and C .
At which point (of the two ) , the electric potential is  more and why  ?
1903709_3109a52bf3c648ccac220272678ac868.PNG



How many quarts are in 10 gallons?



What is scalar quantity 



Why does 1 amu = 1 g/mol?



How can i convert centimeters to meters?



How many pints are in a cup?



How many $$ cm^3 $$ in $$m^3 $$ volume ?



How many cups are in 20 quarts?



How many cups are in a quart



How many cups are in 1/2 a gallon?



A recipe for making creamy pasta sauce calls for 0.75 of cream. Your measuring cup measures cups. How many cups of cream should you use?



How many cups are in a quart?



What is the size of the universe in centimeters?



A recipe calls for 1/2 gallon of punch, 3 pints of club soda, and 2 cups of ice cream. How many quarts does the recipe make?



How do you find out how many feet are in a mile?



How many feet in a mile?



How many feet are in 1/2 of a mile?



How many cups are equivalent to one pint?



How many cups are there in nine ounces?



How many quarts are in a gallon?



How many feet are in 1000 yards?



How many feet are in 2.4 miles?



How many yards are in a tenth of a mile?



How many inches is in 5 yards?



How many feet are in 1 yard?



How many feet is in 3 miles?



.4 miles is how many feet?



What is the force of gravity from jupiter on you at birth compared to the force of gravity from a nearby cobe machine?



How many feet are in a football field that is 100 yards?



How many seconds are in a 24 hour day?



Your walk to school is a half a mile. Approximately how many feet is this?



How do you use dimensional analysis to figure out how many seconds are in 4 years?



How to convert 2.5 radian to degree / minute / second?



How many seconds are there in a year?



A bag of chips is 24 ounces. A serving size is $$\dfrac{3}{4}$$ of an ounce. How many servings are in the bag of chips?



How many seconds are in 7 hours?



How many square feet are in $$100 m^{2}$$ ?



What is the pressure conversion factor for torr to kpa?



How do you calculate formula mass ?



How long does it take for the earth to rotate on its axis?



How many types of quarks are there and what are their names?



How many yards are in 7 miles?



Why does $$1\ amu=1\ g/mol$$?



The official length for a marathon race is 26.2 miles. How many yards long is a marathon? How many feet?



How many yards in a mile?



How many yards are in 5 miles?



How many yards are in a square mile?



How can you calculate mass if density and volume are known ?



A golf ball weighs about 45.9 grams. About how many ounces would a dozen golf balls weigh?



How many yards are in a 1/4 of a mile?



How much is 168 cm in feet and inches?



What is percent error/percent deviation ?



How much is 10 kg is pounds?



How many pints are in a cup?



How many pints is 1 pound?



How do you find volume when given mass ?



8 cups equals how many quarts?



How do you convert 3.82 meters per second to kilometers per hour ?



How do you convert ml to l ?



How do you convert between moles and liters ?



How do you convert grams to moles and moles to grams ?



How do you convert km/h to m/s?



How do you convert 100 g to kg ?



How do you convert 255 mm Hg to atm? What about 620 torr to PSI ?



How do you convert cm to mm ?



How do you convert -70 degrees into radian measure ?



How do you convert miles per hour to meters per minute?



How many nanometers are there in 1 cm ?



How do you convert between moles and liters ?



How do I convert m/s to km or km/h ?



What are some examples of Newton's third law?



What is Newton's third law?



When calculating percent error, what does it mean if I get a negative number for mass?



How many ounces in $$1/4$$ of a pound?



How do you convert SI units ?



How many seconds are in a 24 hour day ?



How many pints are in a quart?



How do you convert 4.5 gal to L? How about to mL ?



What is the SI unit of mass?



How many minutes are in 1 full week?



Is it possible to add a scalar to a vector? Why or why not?



Is one tenth of a foot a common unit of measurement?



Convert $$16$$ degree celsius into fahrenheit.



Can someone lend me a hand in explaining sig figs involving different units?
How would I solve and express the answer in sig figs?
1906044_74772db28f4642468d5a1445174c71ea.PNG



How are astronomical units, light years and parsecs related?



Derive the formula for Celsius to Fahrenheit?



Can u derive the formula for orbital velocity with proper explanation?



What is meant by 'terminal velocity' for a skydiver, and what forces are acting when a skydiver is falling at terminal velocity?



An elastic cord is $$61\ cm$$ long when a weight of $$75\ N$$ hangs from it but is $$85\ cm$$ long when a weight of $$210\ N$$ hangs from it. What is the "spring" constant $$k$$ of this elastic cord?



A machine gun fires $$10$$ rounds per second. The speed of the bullets is $$300\ m/s$$. What is the distance in the air between the flying bullets?



A sprinter runs around a $$440$$ meter circular track in $$49$$ seconds. What is her average speed? What is her average velocity? Can you tell anything about her instantaneous velocity $$5$$ seconds after the start?



An atom of gold has a mass of approximately $$3.25 \times  10^{-22}$$ grams. What is the mass $$1000$$ atoms of gold?



A value of 345mm is a measure of?



A particle moves along a straight line with velocity given by $$v(t)= 7 - (1.01)^{-t^2}$$ at time $$t \geq 0$$. What is the acceleration of the particle at time $$t=3$$?



Convert 18 km/h to m/s? Answers with steps



How are density mass and volume related?



Which are the largest atoms?



How does force change the shape of an object?



A car traveling $$85\ km/hr$$ strikes a tree. The front end of the the car compresses and the driver come to rest after travelling $$0.80\ m$$. What was the average acceleration of teh driver during the collision?



How do I get the molar mass of urea?



How many atoms in an $$18 \ g$$ mass of glucose?



How many formula units are in $$0.335$$ g CaO?



Ebonae's fish tank holds 40 gallons. How many quarts does the fish tank hold?



How can acceleration be negative?



Explain how biological preparedness can be applied to taste aversions and phobias?



How does impulse affect momentum?



How does the atomic number affect atomic radius?



How do chemistry and biology relate?



Are atomic mass, formula mass, and molar mass the same thing?



How do you draw $$s, p, d, f$$ orbitals?



How do you calculate mole fractions?



Every Wednesday Carla runs 2.5 miles. How many feet did she run?



How do you use scientific notation?



How many inches are in $$\dfrac{1}{4}$$ yard?



How do you find the magnitude of the acceleration of the particle?



How many inches are in 1$$\dfrac{ 1}{3}$$ yards?



How many cents is 3 quarters?



How fast does earth rotate near the equator?



How many cubic centimeters are in an $$8.00\ oz$$ bottle of cough medicine?



How many $$cm^{3} $$ are the in $$ 1m^{3} $$ ?



How many inches is in 1 yard?



How many inches is there in $$\dfrac{1}{8}$$th of a yard?



How many cups are in a gallon?



How many cups are in $$\dfrac{1}{2}$$ a gallon?



How many cubic centimeters would you need to have 1 mole of aluminum?



How many feet are in 4 miles?



How many feet are in 2.4 miles?



How many feet are in $$\dfrac{1}{2}$$ of a mile?



How many feet is 15 miles?



How many feet are in .55 miles?



How many degrees celsius equals one degree fahrenheit?



How many kilograms are equal to 5,000 grams?



How many kilometers is 1.7 miles?



How many degrees Celsius is 67 F?



How many degrees = 1 radian?



How many feet in a mile?



How many km are in 5.6mm?



How many gallons are in 60 ounces?



How many earth years are in 1 light year?



How many meters are in a yard?



How many litres are in a gallon?



How many gallons are in 101.4 fl oz?



How many light years away is the sun from Jupiter?



How many fluid oz. are in a gallon?



How many feet is 33 miles?



How many grams are in 2000 mg?



How many miles are in $$100$$ feet?



How many millimeters are in 50 cm?



How many grams are in 40 hectograms?



How many milliliters are in a cubic meter ?



How many micrograms make 1 kg?



How many microliters are in 41.0 mL?



How many meters is 120 cm?



How many meters in a mile?



How many grams are in one atomic mass unit?



How many square feet are in $$100m^2$$?



How many millimeters are in an inch ?



How long in meters is 670 nanometers?



How many minutes are in $$1.25$$ hours?



How is solubility expressed in units of measurement?



How many ml is in 2 liters?



How many minutes are in 0.5 hour?



How many minutes are there in 2.8 hours?



How many nanometers are there in 1 cm?



How many minutes are in 1 full week?



How many milliliters are equivalent to $$2.7$$ liters?



How long is an eon in years?



How many arcseconds are in a degree?



How long is 33 inches added to 4 feet 7 inches?



How many arcseconds are in $$1^{\circ}$$ ?



How many significant figures are in the measurement 0.0034 kg?



How to convert $$ 2.5 $$ radian to degree/minute/second?



How many ounces are equivalent to a quarter of a pound?



How many significant figures are in the measurement 2103.2 g?



How many $$\dfrac{1}{3}$$ cups do you need to make $$\dfrac{1}{2}$$ cup?



How long is $$\dfrac{7}{10}$$ of a mile, in feet?



How many base SI units are there?



How many quarts are in 12 cups?



How many quarters does an hour have?



How many ounces is $$0.2\, lbs$$?



How many ounces in 1/8 pounds?



How many ounces are in one and a half quarts?



How many quarts are in 10 gallons ?



How many ounces is in 500 mL?



How many ounces in 1/4 of a pound?



How many centimeters are in 7.2 inches?



How many pints are equivalent to 3 gallons?



How many seconds are in $$3.5$$ years?



How many seconds are there in $$35$$ minutes?



How many pints are in 7 quarts?



How many seconds are there in 2.5 hours?



How many centimeters are in $$3$$ inches?



How many seconds are in a 24 hour day?



How much is $$3$$ Kelvin?



How many yards are in a tenth of a mile?



How many centimeters are in a inch?



How many yards are in a $$1/4$$ of a mile?



How many yards are in $$5$$ miles?



How many yards in a mile?



How many yards go into one and three fourths miles?



How many centimeters are there in 2 kilometers?



How many centimeters are there in $$1.23 \times 10^{-6}$$ kilometers?



How many yards are in $$7$$ miles?



How much is $$325 F$$  in $$^0C$$?



How much is $$90 C$$ in Fahrenheit?



How much is $$70$$ degrees Fahrenheit in Celsius?



How much is $$10 kg$$ in pounds?



How much is $$168 cm$$ in feet and inches?



How much is $$23kg$$ in pounds?



How to convert L to $$ dm^3$$ and ml to $$ cm^3$$ ? 



Please prove $$1\ debye = 10^{-18} \  esu \ cm = 3.335 \times 10^{30} \ C - m$$ ( coulomb meter), 



How to you convert $$ 5 $$ radians to degrees?



How much is $$63 kg$$ in pounds?



What are polar coordinates used for in real life?



What are the steps of the scientific method?



Mr. Brady's new car get sixty miles to the gallon. In the metric system gas consumption is measured in liters per $$100$$ kilometers, how do you make the conversion?



What determines when a system reaches equilibrium? What observations can be made about a system once equilibrium has been established?



What did Leibniz contribute to the development of calculus?



The diameter of an atoms is approximately $$ 1.10 ^{-8} cm $$ . What is this diameter when expressed in nanometers ? 



What are the appropriate units for the Sun's luminosity?



On the blueprint of a house, $$48$$ millimeters represents $$7$$ meteres. The length of the living room is $$60 $$ millimeters on the blueprint. What is the actual length of the living room? 



One inch equals $$2.54$$ centimeters. How do you find the length of a newborn, in inches, if it measures $$45.7$$ centimeters?



Is one joule per second equivalent to one watt?



What is SI unit conversion?



What is megahertz a measurement of?



What do quantitative and qualitative measurements mean in science?



What is Radian Measure?



What is the difference between morphology and physiology?



What is the difference between intensional orientation and extensional orientation?



What is the Fahreheit equvialent of $$15$$ degrees celsius ?



What is the correct order from shortest to longest for these units of measure?Angstrom, astronomical unit, centimeter, kilometer, lightyear, micron, nanometer, parsec?



What is the basic SI unit of density?



What is systemic physiology?



What is the Kelvin temperature scale?



What SI units are used to measure density?



What period corresponds to $$ 500 Hz$$?



What is the temperature $$-34^0C$$ expressed in kelvin?



What is the distance from earth to the sun in scientific notation?



What SI units are used to measure power?



What is the temperature, in degrees Celsius, that is equivalent to a temperature of $$40^0F$$?



What is the mass of a $$132\ lb$$ human in kilograms?



What is the basic unit of length in the SI system?



How do you convert 7.8 km to miles?



Why is the metric system important?



What units of measurement are used to describe wavelengths?



What units can measure density?



What metric unit is used to measure distance?



What is the unit used to measure period called?



A mile is $$5280\text{ ft}$$ long. $$1\text{ ft}$$ is approximately $$0.305 m$$. How many meters are there in a mile? How many kilometres $$\text{(km)}$$ are there in a mile?



What is the unit symbol for a nanometre?



Why is the scientific method important to follow?



Who invented gravity ?



What is linear mass density?



Which of the following are vectors and which are scalars: distance, mass, time, weight, volume, density, speed, velocity, acceleration, force, temperature and energy?



Why $$[CuCl_4]^{2-}$$ has a flattened tetrahedral structure, not regular tetrahedron and $$[CoCl_4]^{2-}$$ is tetrahedron?



How many inches is in 5 yards?



Why do scientists prefer the SI units over the old English system of measurement?



$$0.4$$ miles is how many feet?



An average human body temperature is $$98.6^{\circ}F.$$ What is average human body temperature in Kelvins?



How many quarts are in $$10$$ gallons?



Why is a universal system of measurement necessary in science?



What is mu in physics?



Why do catalysts affect collision theory?



How many ounces are in 1/4 of a gallon?



How do you convert $$105$$ degrees fahrenheit to celsius?



What are units of measurement?



How do atmospheric pressure and elevation affect boiling point?



Does the coefficient of restitution change?



How do you convert milliliters to liters?



How do you convert $$2.3$$ cm to mm?



How do you convert 90 inches to yards?



Why are astronomical units used?



How much is 70 degrees Fahrenheit in Celsius?



To convert a temperature in degrees Celsius to degrees Fahrenheit, multiply the Celsius temperature by $$\dfrac{9}{5} $$ and then add $$ 32^{\circ}$$ ls a temperature in degrees Celsius proportional to its equivalent temperature in degrees Fahrenheit?



How do you convert the measurement of 2 days into seconds?



How many nanometers are there in 1 cm?



How do you convert  $$ 45^{o}C $$ to Fahrenheit?



What is 29 degrees celsius in fahrenheit?



How do you convert 360 degrees to radians?



How to calculate rotational speed?



How long would it take to bicycle 45 miles at an average speed of 15 miles per hour?



What is the Fahrenheit equivalent of 15 degrees Celsius?



How many moles are there in 28 grams of $$CO_2$$?



What function do Protons, Neutrons, and Electrons have in an atom?



How many gallons are in 101.4 fl oz?



What is a quantitative measurement and what is a qualitative measurement?



A stone is dropped freely, while another thrown vertically downward with an initial velocity of 2m/s from the same point, simultaneously. What is the time required by them to have a distance of 22 m between them ?



What are the seven fundamental units?



How do you find the slope and y intercept of y = x?



Find the number of atom present in $$PO_4^{ -3}$$ ions ?



How do you estimate carrying capacity of a population?



Why is the rusting of an iron pole not a physical change ?



The cells of unicellular organisms are what?



What units of measurement are used for the combined gas law?



What is the chemical formula for ATP?



A wrench with a length of 54cm is being used to unscrew a 6cm bolt. If a torque of 90Nm is needed to overcome the friction keeping the bolt in place, what is the minimum torque that must be applied to the wrench to unscrew the bolt?



Which Among The Following Algorithms Is Designed Based On The Feistel Cipher?



What Is Density ????



How does calculus relate to chemistry?



What is the correct order from shortest to longest for these units of measure?Angstrom, astronomical unit, centimeter, kilometer, lightyear, micron, nanometer, parsec?



which of the following sets of concurrent forces may be in equilibrium?
$$ 1) F_1 = 3N , F_2 =5N , F_3= 1N $$
$$2) F_1 =3N , F_2=5N , F_3= 6N$$



Displacement is scalar or vector quantity ?



The force of gravity is measured in units called ____________ (Newtons/watts).



Give a physical quantity which has no units ?



Give two real life examples of gradient divergence and curl.



Define the term speed. what are its various units? is it a scalar or vector quantity?



What is delphi technique explain with suitable example ?



What is the relation between Joule and calorie?



How many seconds are there in one week



Write the two basic principal in physics.



Difference between bust and chest measurement



Definition of Motion



What is the science and what is physically?



What is orbit and orbital?



Convert $$1$$ lakh into Million.



11.25m into mm, converted as directed



Convert into hour 1 hour 20 min



What is the smallest particle of matter - a)atom b)molecule Pls explain the answer.



Good book for organic chemistry?



Who is the Isaac Newton



Define Momentum. It is a scalar and vector quantity ? give its unit and dimension



What can't be measured? is it  not important ? Justify​.



Find Time(In hrs.)

Speed = 20 kilometer per hour(km/h)
Distance = 100 Kilometer(km)



Explain with the help of an activity that matter is made up of particles



How are given mass, molar mass and number of moles related to each other?



All the important definition of chapter 1 for class 10 Science 1st chapter chemistry.



Why is the unit of temperature called a fundamental unit?



A student studies that convex lens always forms virtual image irrespective of its position. What causes the convex mirror to always form a virtual image?



Examples of scalar and vector quantities list.



What is the effect of temperature on molarity?



Write the relationship between kilowatt-hour and joule



What is the unit of electric potential?



Define Latent heat of vaporisation.



List two properties that liquids have in common with solids.



The relationship and strength of the four fundamental forces (gravitational, electromagnetic, weak nuclear, And strong nuclear)



Change of gaseous state directly to solid state without going through liquid sate is called _____________________ .



Do we sweat more on a dry day or humid day ? Justify your reason.



The absolute scale of temperature is Kelvin. Water freezes at 273 K. and boils at 373 K. hence find out the value of 40-degree Celsius temperature in the Kelvin scale.



What is hygrometer?



Compare and contrast action-reaction forces and balanced forces.



Why do we see water droplets on the outer surface of a glass containing ice cold water?



Time taken to fix a broken build is measured using _________.



Write the $$SI$$ units of resistance?



The standard unit of mass is the _______.



What is the relationship between astronomical unit and light year



Write any three points of difference between $$'G $$' and $$'g'$$.



Define atomic mass unit?



What is the full form of physics?



Examples of periodic and non periodic changes



Acceleration is a vector quantity ,which indicates that its value



Name the forces acting on the car sticking to an electromagnet in a Junkyard. Which one of them is larger?



Atomic radius is measured in ...



A particle start from rest on circular path with constant tangential acceleration.  Find the ratio of centripetal acceleration to the tangential acceleration after one revolution.



How many feet are in a football field that is 100 yards?



What is the unit of viscosity? Please explain.



One year on Mercury is equal to $$87.97$$ Earth days. One year on Pluto is three times the length of one Mercury year minus $$16.21$$ days. How long is one year on Pluto?



A car derives north for $$35$$ minutes at $$85\ km/hr$$ and then stop for $$15$$ mins. The car continues north travelling $$130\ km$$ in $$2$$ hours. What is the total displacement and average velocity?



How do intermolecular forces affect evaporation?



Aneesha travels at a rate of $$50$$ miles per hour. Morris is traveling $$3$$ feet per second less than Aneesha. Which is the best estimate of the speed Morris is traveling?



How was it determined that a parsec is $$ 3.26 $$ light years?



What is a clever way to remember anthimeria and periphrasis?



SI unit of potential energy?



What is one atmosphere of pressure?



What is the SI unit of electric charge?



What bases are purines?



What are the $$6$$ models of the atom?



On a scale drawing, $${1}/{4}$$ inch $$=1$$ foot. What are the dimensions on the scale drawing for a room that is $$18$$ feet by $$16$$ feet?



What is the unit used for Water Vapor?



What is the SI unit used to measure amount of substance?



Water is leaking out of an inverted conical tank at the rate of 10,000 cm$$^3$$/min at the same time that water is being pumped into the tank at a constant rate. The tank has a height of 6m and the diameter at the top is 4m. If the water level is rising at a rate of 20 cm/min when the height of the water is 2m, how can I find the rate at which water is being pumped into the tank.?



Write the SI unit of co efficient of static friction



Give some examples of electrostatic force



A circular curve of highway is designed for traffic moving at $$92 km/h$$. When assumed the traffic consists of cars without negative lift ?
(a) If the radius of the curve is $$150 m$$, what is the correct angle of banking of the road? 

(b) If the curve were not banked, what would be the minimum coefficient of friction between tires and road that would keep traffic from skidding out of the turn when traveling at $$92 km/h$$?



How does Newton's second law relate to inertia ?



How to calculate the force of gravitational attraction between a person (mass $$=75\ kg$$) & Earth (mass $$5.98\times 10^{24}\ kg$$ and mean radius $$6.37\times 10^{6}m$$) ?



Class 8 General Knowledge Extra Questions