CBSE Questions for Class 11 Engineering Physics Motion In A Plane Quiz 6 - MCQExams.com

An old man and a boy are walking towards each other and a bird is flying over them as shown in the figure. Find the velocity of bird as seen by the boy.
301677_e3f89bdce68940ae9aafca6eb0dcaced.png
  • $$12{\hat{j}}$$
  • $$16{\hat{j}}$$
  • $$-12{\hat{j}}$$
  • $$-16{\hat{j}}$$
The position vector of  a particle moving in x-y plane is given by 
$$\displaystyle F= (A\sin \omega t)i+(A\cos \omega t)j$$ then motion of the particle is 
  • $$SHM$$
  • on a circle
  • on a stralght line
  • with constant acceleration
The angular velocity of rotation of hour hand of a watch is how many times the angular velocity of Earth's rotation about its own axis?
  • Three
  • Four
  • Two
  • Six
The rear wheels of a car are turning at an angular speed of $$60$$ rad/s. The brakes are applied for $$5$$s, causing a uniform angular retardation of $$8\, rad/s^{-2}$$. The number of revolutions turned by the rear wheels during the braking period is about:
  • $$48$$
  • $$96$$
  • $$32$$
  • $$12$$
Work done upon a body is a vector quantity. State true or false.
  • True
  • False
A wheel of radius 1 m rolls forward half a revolution on a horizontal ground. The magnitude of the displacement of the point of the wheel initially in contact with the ground is
  • $$2 \pi m$$
  • $$\sqrt2 \pi m$$
  • $$\sqrt{\pi^2 +4} m$$
  • $$\pi m$$
Which one of the following is not a vector ?
  • Velocity
  • Acceleration
  • Force
  • Energy
A cyclist taking a turn bends inside because
  • He feels pleasure in doing so
  • He increases speed in doing so
  • He obtains necessary centripetal force
  • He avoids accidents
How is average velocity found by using velocity-time graphs?
  • $$\text{Average velocity} = \dfrac{\text{Area under v-t graph in the time-interval}}{\text{time interval}}$$
  • $$\text{Average velocity} = \dfrac{v(t_2)-v(t_1)}{t_2-t_1}$$
  • $$\text{Average velocity} = \dfrac{v(t_2)+v(t_1)}{2}$$
  • None of the above
Given that $$\vec {P} + \vec {Q} + \vec {R} = \vec {0}$$. Two out of the three vectors are equal in magnitude. The magnitude of the third vector is $$\sqrt {2}$$ times that of the other two. Which of the following can be the angles between these vectors?
  • $$90^{\circ}, 135^{\circ}, 135^{\circ}$$
  • $$45^{\circ}, 45^{\circ}, 90^{\circ}$$
  • $$30^{\circ}, 60^{\circ}, 90^{\circ}$$
  • $$45^{\circ}, 90^{\circ}, 135^{\circ}$$
A ball is thrown vertically upwards. Which of the following plots represents the speed-time graph of the ball during its flight if the air resistance is not ignored?
For a particle in a uniformly accelerated circular motion 
  • Velocity is radial and acceleration has both radial and transverse components
  • Velocity is transverse and acceleration has both radial and transverse components
  • Velocity is. radial and acceleration is transverse only
  • Velocity is transverse and acceleration is radial only
The driver of a car travelling at velocity $$v$$ suddenly see a broad wall in front of him at a distance $$d$$. He should :
  • Brake sharply
  • Turn sharply
  • Both (a) and (b)
  • None of these
A particle is executing a two dimensional motion. What is the minimum number of velocity-time graphs required to study the motion of the particle using graphs?
  • 1
  • 2
  • 3
  • 4
A and B travel around a circular path at uniform speeds in opposite direction starting from the diagrammatically opposite point at the same time. They meet each other first after B has traveled 100 meters and meet again 60 meters before A complete one round. What is the circumference of the circular path?
  • $$240m$$
  • $$360m$$
  • $$480m$$
  • $$300m$$
A wheel has a speed of 1200 revolutions per minute and is made to slow down at a rate of 4 rad/s$$^2$$. The number of revolutions it makes before coming to rest is:
  • 143
  • 272
  • 314
  • 722
Uniform linear motion is a/an _______ motion while uniform circular motion is a/an _______ motion. 
  • accelerated, non accelerated
  • non accelerated, accelerated
  • deviated, retarded
  • uniform, retarded
A wheel has a speed of $$1200$$ revolution per minute and is made to slow down at a rate of $$4\;rad/s^2$$. The number of revolution it makes before coming to rest is
  • $$143$$
  • $$272$$
  • $$314$$
  • $$722$$
A particle is moving with constant speed $$v$$ in circle. What is the magnitude of average velocity after half rotation?
  • $$2v$$
  • $$2\dfrac{v}{\pi}$$
  • $$\cfrac{v}{2}$$
  • $$\cfrac{v}{2\pi}$$
When a ceiling fan is switched on, it makes 10 revolution in the first 3 s. Assuming a uniform angular acceleration, how many rotation it will make in the next 3 s?
  • 10
  • 20
  • 30
  • 40
A wheel has angular acceleration of $$3.0\ rad/s^2$$ and an intial angular speed of $$2.00\ rad/s$$. In a time of $$2s$$ it has rotated through an angle (in radians) of:
  • $$6$$
  • $$10$$
  • $$12$$
  • $$4$$
Certain neutron stars are believed to be rotating at about $$1$$rev/s. If such a star has a radius of $$20$$km, the acceleration of an object on the equator of the star will be.
  • $$20\times 10^8m/s^2$$
  • $$8\times 10^5m/s^2$$
  • $$120\times 10^5m/s^2$$
  • $$4\times 10^8m/s^2$$
A wheel which is initially at rest is subjected to a constant angular acceleration about its axis. It rotates through an angle of $$15^o$$ in time $$t$$ $$secs$$. The increase in angle through which it rotates in the next $$2t$$ $$secs$$ is:
  • $$90^o$$
  • $$120^o$$
  • $$30^o$$
  • $$45^o$$
An object is thrown towards the tower which is at a horizontal distance of $$50\ m$$ with initial velocity of $$\displaystyle 10{ ms }^{ -1 }$$ and making an angle $$\displaystyle { 30 }^{ \circ  }$$ with the horizontal. The object hits the tower at certain height. The height from the bottom of the tower where the object hit the tower is ($$\displaystyle g=10{ ms }^{ -2 }$$) :
  • $$\displaystyle \frac { 50 }{ \sqrt { 3 } } \left[ 1-\frac { 10 }{ \sqrt { 3 } } \right] m$$
  • $$\displaystyle \frac { 50 }{ 3 } \left[ 1-\frac { 10 }{ \sqrt { 3 } } \right] m$$
  • $$\displaystyle \frac { 100 }{ \sqrt { 3 } } \left[ 1-\frac { 10 }{ \sqrt { 3 } } \right] m$$
  • $$\displaystyle \frac { 100 }{ 3 } \left[ 1-\frac { 10 }{ \sqrt { 3 } } \right] m$$
A particle moves so that its position vector is given by $$\vec{r}=\cos \omega t \hat{x}+\sin \omega t\hat{y}$$. Where $$\omega$$ is a constant. Which of the following is true? 
  • Velocity an acceleration both are perpendicular to $$\vec{r}$$
  • Velocity and acceleration both are parallel to $$\vec{r}$$
  • Velocity is perpendicular to $$\vec{r}$$ and acceleration is directed towards the origin
  • Velocity is perpendicular to $$\vec{r}$$ and acceleration is directed away from the origin.
When the tail of vector A is set at the origin of the $$XY$$ -axis, the tip of A reaches $$(3,6)$$. When the tail of vector B is set at the origin of the XY -axis, the tip of Breaches $$(-1,5).$$ If the tail of vector $$\vec {AB}$$ were set at the origin of the $$XY$$ - axis, what point would its tip touch?  
  • $$(2,11)$$
  • $$(2, 1)$$
  • $$(-2,7)$$
  • $$(-4, -1)$$
  • $$(4,11)$$
Which of the following are vector quainities?
  • Force
  • Velocity
  • Momentum
  • All of the above
Which of the following vectors best represents the vector A + B ?
489760_6e13f8e63ff245c984216051ef4ef7d7.png
Find out the angular acceleration of a washing machine, starting from rest, accelerates within $$3.14 s$$ to a point where it is revolving at a frequency of $$2.00 Hz$$.
  • $$0.100 {rad}/{{s}^{2}}$$
  • $$0.637 {rad}/{{s}^{2}}$$
  • $$2.00 {rad}/{{s}^{2}}$$
  • $$4.00 {rad}/{{s}^{2}}$$
  • $$6.28 {rad}/{{s}^{2}}$$
Two coins are sitting on a horizontal disk, which is rotating at a constant speed.
One coin is a penny located halfway between the center of the disk the edge. The other coin is a dime located at the edge of the disk.
How does the magnitude of the dime's acceleration compare to the magnitude of the penny's acceleration?
  • The magnitude of the acceleration of the dime is the same as the magnitude of the acceleration of the penny
  • The magnitude of the acceleration of the dime is twice the magnitude of the acceleration of the penny
  • The magnitude of the acceleration of the dime is half the magnitude of the acceleration of the penny
  • The magnitude of the acceleration of the dime is four times the magnitude of the acceleration of the penny
  • The magnitude of the acceleration of the dime is one-fourth the magnitude of the acceleration of the penny
The objects pictured above are coins moving around on a record player. The coins are not sliding on the record player surface. Which coins is moving faster and how many times faster it is moving than the other one ?
The space between each vertical line along the horizontal arrow is one-seventh the radius of the circular record player surface.
492517_098f3f4a32a44cf39e463ba02ed7a01d.png
  • 1-three times faster than slowest
  • 3-five-seventh's faster than slowest
  • 3-five times faster than slowest
  • 1-five-seventh's faster than slowest
  • 2-three-seventh's faster than slowest
A skater moves over ice in circular path at a constant speed. He later moves over ice in a circular path at a constant speed, but this time with five times as much acceleration as before.
What single difference in the motion of the skater might have caused his acceleration to be five times as great?
  • He may have been moving five times as fast as before
  • He may have been moving around a curve with five times the radius of the original circular path.
  • He may have been moving a little over two times as fast
  • He may have been moving around a curve with a radius just over twice as much as the original radius.
  • he may have been wearing more massive skates.
A dog walks $$140\ m$$ due east and then turns west and runs $$65\ m$$. He then turns north and trots $$40\ m$$. After completing his journey, he is $$85\ m$$ northeast of his home. When he hears his master's call, he runs directly home.
Which part of the trip is a negative vector?
  • The eastward leg
  • The westward leg
  • The northward leg
  • The distance from home
  • The distance to home
Which of the following are vector quantities?
  • Magnetic moment
  • Magnetic permeability
  • Magnetic induction
  • Magnetic pole strength
Starting from rest, a fan take five seconds to attain the maximum speed of 400 rpm. Assume constant acceleration, find the time taken by  the fan attaining half the maximum speed. 
  • 11 s
  • 2.0 s
  • 5.0 s
  • 2.5 s
If the horizontal range is given as 12.8 m, then the equation of parabolic trajectory can be given by:
  • $$16x - \dfrac{5x^2}{4}$$
  • $$16x - \dfrac{3x^2}{4}$$
  • $$14x - \dfrac{5x^2}{4}$$
  • $$12x - \dfrac{5x^2}{4}$$
The velocity time graph of a particle moving along a straight line has the form of a parabola $$t^{2}-6t+8$$ m/s. Find the velocity (in m/s) when acceleration of particle is zero :
  • $$-1$$
  • $$-2$$
  • $$-3$$
  • $$-4$$
If the angle of projection is $$60^0$$, the equation of trajectory can be given by
  • $$\sqrt {2} x- \dfrac{gx^2}{2}$$
  • $$\sqrt {3} x- \dfrac{gx^2}{4}$$
  • $$\sqrt {3} x- \dfrac{2gx^2}{u^2}$$
  • $$\sqrt {3} x- \dfrac{gx^3}{2}$$
Equation of oblique projectile can be written as:
  • $$y=xtan\theta(1-\dfrac{x}{T})$$
  • $$y=xtan\theta(1-\dfrac{x}{R})$$
  • $$y=xsin\theta(1-\dfrac{x}{R})$$
  • $$y=xtan\theta(1-\dfrac{x}{H})$$
 A motor of an engine is rotating about its axis with an angular velocity of $$100$$ rev/min . It comes to rest in $$15$$ s, after being switched off. Assuming constant angular deceleration, calculate the number of revolutions made by it before coming to rest. 
  • $$10.5$$
  • $$12.5$$
  • $$15.0$$
  • $$20.5$$
A  wheel rotates with a constant acceleration of $$ 2 \ \ rads^{-2}$$. If the wheel starts from rest, how many revolution will it make in  the first $$10$$ seconds? 
  • 8
  • 12
  • 16
  • 20
The ratio between the length and the breadth of a rectangular park is 3 :If a man cycling along the boundary of the park at the speed of 12 km/hr completes one round in 8 minutes, then the area of the park (in sq. m) is:
  • 15360
  • 153600
  • 30720
  • 307200
Find the change in velocity of the tip of the minute hand (radius = $$10 cm$$) of a clock in $$45$$ minutes. (in cm/min)
  • $$\pi \dfrac{\sqrt{2}}{3}$$
  • $$\pi \dfrac{\sqrt{2}}{2}$$
  • $$\pi \dfrac{\sqrt{3}}{3}$$
  • $$\pi \dfrac{2}{3}$$
A horse runs on a circular track of length $$720$$ metres in $$20$$ seconds and returns to the starting point. Calculate the average speed
  • $$36\ metre/second$$
  • $$0\ metre/second$$
  • $$18\ metre/second$$
  • $$72\ metre/second$$
A particle moves along a circle of radius '$$r$$' with constant tangential acceleration. If the velocity of the particle is '$$v$$' at the end of second revolution, after the revolution has started then the tangential acceleration is
  • $$\dfrac{v^2}{8 \pi r}$$
  • $$\dfrac{v^2}{6 \pi r}$$
  • $$\dfrac{v^2}{4 \pi r}$$
  • $$\dfrac{v^2}{2 \pi r}$$
If a vector $$A$$ having a magnitude of $$8$$ is added to a vector $$B$$ which lies along x-axis, then the resultant of two vectors lies along y-axis and has magnitude twice that of $$B$$. The magnitude of $$B$$ is
  • $$\cfrac { 6 }{ \sqrt { 5 } } $$
  • $$\cfrac { 12 }{ \sqrt { 5 } } $$
  • $$\cfrac { 16 }{ \sqrt { 5 } } $$
  • $$\cfrac { 8 }{ \sqrt { 5 } } $$
The locus of a projectile relative to another projectile is a
  • straight line
  • circle
  • ellipse
  • parabola
In the entire path of a projectile, the quantity that remains unchanged is
  • Vertical component of velocity
  • Horizontal component of velocity
  • Kinetic energy
  • Potential energy
  • Linear momentum
When a ceiling fan is switched off, its angular velocity reduces to half its initial value after it completes $$36$$ rotations. The number of rotations it will make further before coming to rest is   Assuming angular retardation to be uniform
  • $$10$$
  • $$20$$
  • $$18$$
  • $$12$$
If the position vector $$\overrightarrow{a}$$ of the point $$(5, n)$$ is such that $$|\overrightarrow{a}|=13$$, then the value/values of n be
  • $$\pm 8$$
  • $$\pm 12$$
  • 8 only
  • 12 only
0:0:1


Answered Not Answered Not Visited Correct : 0 Incorrect : 0

Practice Class 11 Engineering Physics Quiz Questions and Answers