CBSE Questions for Class 11 Engineering Physics Gravitation Quiz 2 - MCQExams.com

Acceleration due to gravity ---------- with height from the surface of the earth.
  • Decreases
  • Increases
  • Remains constant
  • Cannot say
Escape velocity of a particle depends on its mass m as
  • $$m^2$$
  • $$m$$
  • $$m^0$$
  • $$m^{_1}$$
SI unit of G is $$Nm^{2}kg^{-2}$$.Which of the following can also be used as the SI unit of G?
  • $$m^3 kg^{-1} s^{-2}$$
  • $$m^2 kg^{-2} s^{-1}$$
  • $$m kg^{-1} s^{-1}$$
  • $$m^3kg^{-3}s^{-2}$$
The value of gravitational acceleration g at the center of the earth is:- 
  • Infinite
  • $$\displaystyle 9.8{ m }/{ { s }^{ 2 } }$$
  • $$\displaystyle 32.2{ m }/{ { s }^{ 2 } }$$
  • Zero
The value of '$$g$$' is zero
  • At the top atmosphere
  • At $$20 km$$ below the surface of the earth
  • At $$20 km$$ above the surface of the earth
  • At the centre of the earth
The ratio of the value of G in SI units to CGS units is
  • $$10^3:1$$
  • $$10^2:1$$
  • $$10^{-2}:1$$
  • $$10^{-3}:1$$
The value of G depends on
  • the nature of the interacting bodies
  • the size of the interacting bodies
  • the mass of the interacting bodies
  • none of these
Where will a body weigh minimum?
  • At a height of $$100 m$$ above the earth's surface
  • At the earth's surface
  • At a depth of $$100 m$$ below the earth's surface
  • At the centre of the earth
The value of G does not depend on
  • nature of the interacting bodies
  • size of the interacting bodies
  • mass of the interacting bodies
  • all the above
The value of $$g$$
  • Decreases with height from earth's surface
  • Increases with height from earth's surface
  • Remain unchanged with increase of height from earth's surface
  • None of these
The three laws of planetary motion were given by:
  • Einstein
  • Kepler
  • Copernicus
  • Tycho Brahe
Asteroids are
  • A group of small heavenly bodies, forming a belt rotating round the sun
  • Starts forming a recognizable pattern
  • Solid bodies from the outer space
  • A large cluster of stars distributed in the universe in an irregular form
The maximum value of $$g$$ is
  • At the poles
  • At the top of the Mounts Everest
  • At the equator
  • Below the sea level
A body weighs 60 kg on the earth's surface. What would be its weight at the centre of the earth?
  • 60 kg-wt
  • 6 kg-wt
  • 60$$\times$$9.8 kg-wt
  • zero
A raised hammer possesses
  • K.E. only
  • Gravitational P.E,
  • Electrical energy
  • sound energy
The variation of g with height or depth (r) is shown correctly by which of the following graphs. (where R is the radius of the earth).
The evidence to show that there must be force acting on Earth and directed towards the Sun is.
  • phenomenon of day and night
  • apparent motion of the Sun around the Earth
  • revolution of Earth around the Sun
  • deviation of the falling bodies towards east
Which of the following units can be used to express G?
  • N Kg$$^{-2}$$
  • Nm$$^{-2}$$ Kg$$^{2}$$
  • Nm$$^{2}$$ Kg$$^{-2}$$
  • Nm$$^{-2}$$ Kg$$^{-3}$$
In a vacuum on the earth surface, all freely falling bodies 
  • have the same speed
  • have the same velocity
  • have the same force
  • have the same acceleration
At a height equal to earth's radius, above the earth's surface, the acceleration due to gravity is
  • g
  • $$\displaystyle \frac{g}{2}$$
  • $$\displaystyle \frac{g}{4}$$
  • $$\displaystyle \frac{g}{8}$$
At the centre of the earth, the value of g becomes
  • zero
  • unity
  • infinity
  • none of these
State whether true or false.
As the distance of the planet from the sun increases, the period of revolution decreases.
  • True
  • False
Calculate the weight of the block at a distance of four times of Earth radii from the center of the Earth. It is given that g is the acceleration due to gravity at the surface of Earth and mass of the block is m.
  • 16mg
  • 4mg
  • 2mg
  • $$\dfrac{1}{4}$$mg
  • $$\dfrac{1}{16}$$mg
Fill in the blanks:
Value of gravitational constant (G) on moon is __________ as on earth.
  • Greater
  • Smaller
  • Same
  • None
Kepler's laws of motion are applicable to _______
  • All objects
  • Planets
  • Objects on earth
  • Objects on moon
If the radius of the earth were to shrink by $$2$$%, its mass remaining the same, the acceleration due to gravity on the earth's surface would
  • decrease by $$2$$%
  • increase by $$2$$%
  • increase by $$4$$%
  • decrease by $$4$$%
When an object is far from earth, 'g' is calculated by the formula:
  • $$G\frac{M\times m}{R^2}$$
  • $$G\frac{M}{R^2}$$
  • $$G\frac{M\times m}{d^2}$$
  • $$G\frac{M}{d^2}$$
When an object is close to the surface of earth the acceleration due to gravity is calculated by using the formula
  • $$\frac{F\times d^2}{M\times m}$$
  • $$G\frac{M\times m}{d^2}$$
  • $$G\frac{M}{R^2}$$
  • $$G\frac{M}{d^2}$$
The escape velocity nearer to the surface of a planet of radius $$6800$$ km and mass $$\displaystyle 8 \times  {10} ^{24} $$ kg is ____ $$\displaystyle {kms} ^{-1} $$
  • $$32.5$$
  • $$21.2$$
  • $$12.5$$
  • $$11.2$$
Universal gravitational constant $$G$$ is proportional to distance $$r$$ between two masses as-
  • $$r^2$$
  • $$r$$
  • $$1/r$$
  • does not depend upon $$r$$
Value of universal gravitational constant $$G$$ in CGS unit is-
  • $$6.67\times 10^{8}cm^3g^{1}s{}$$
  • $$6.67\times 10^{8}cm^3g^{-1}s^{-2}$$
  • $$6.67\times 10^{9}cm^3g^{1}s^{2}$$
  • $$6.67\times 10^{7}cm^3g^{-1}s^{2}$$
The universal law of gravitation must be applicable to 
  • The earth and the moon.
  • The planets around the Sun.
  • Any pair of bodies.
  • The earth and the apple.
Value of acceleration due to gravity of earth is maximum :
  • At centre of earth
  • At surface of earth
  • At a height of 50 km from earths surface
  • At a height of 12 km from earths surface
The ratio of the value of gravitational constant $$G$$ between Earth and Moon system and Earth and Sun system is:
  • Greater than $$1$$
  • Less than $$1$$
  • Equal to $$1$$
  • Can't be determined
The energy required to remove a body of mass 'm' from earths surface is/are equal to:
  • -GMm/R
  • mgR
  • -mgR
  • none of these.
State whether true or false.
The weight of a freely falling body from a very large height is always constant.
  • True
  • False
 The escape velocity of projection from the earth is approximately ($$R = 6400 km$$).
  • $$7 km/s$$
  • $$112 km/s$$
  • $$11.2 km/s$$
  • $$1.1 km/s$$
Motion of planets in solar system is an example of conservation of :
  • Momentum
  • Velocity
  • Angular momentum
  • Energy
The earth retains its atmosphere because
  • The earth is sphere
  • The earth has population
  • The escape velocity of molecules is less than the mean speed of molecules
  • The escape velocity of molecules is more than the mean speed of molecules
The value of gravitational acceleration 'g' at a height 'h' above the earth's surface is $$\dfrac{g}{4}$$ then (R = radius of earth)
  • $$h = R$$
  • $$h = \dfrac{R}{2}$$
  • $$h = \dfrac{R}{3}$$
  • $$h = \dfrac{R}{4}$$
The gravitational potential is a 
  • scalar
  • vector
  • scalar based on the mass of the particle
  • scalar or vector depending on the situation
Gravitational potential energy is negative. This implies 
  • Energy is rising along negative x axis
  • A particle is trapped in this potential
  • The particle is moving in the opposite direction
  • Energy is decreasing in the direction of motion of the particle
The value of $$'g'$$ will be $$1$$% of its value at the surface of the earth at a height of $$(R_e = 6400km)$$ -
  • 6400 km
  • 57600 km
  • 12560 km
  • 64000 km
If $$R$$ is the radius of the earth, then the value of acceleration due to gravity at a height $$h$$ from the surface of the earth will become half its value on the surface of the earth if
  • $$h = 2R$$
  • $$h = R$$
  • $$h = (\sqrt {2} + 1)R$$
  • $$h = (\sqrt {2} - 1)R$$
The weight of a body of mass $$3kg$$ at a height of $$12.8 \times 10^6m$$ from the surface of the earth is _______.
  • $$9.75N $$
  • $$1.46N $$
  • $$3.26N $$
  • $$4.36N $$
Two identical spherical masses are kept at some distance. Potential energy when a mass $$m$$ is taken from the surface of one sphere to the other
  • increases continuously
  • decreases continuously
  • first increases, then decreases
  • first decreases, then increases
What is the percentage decrease in the weight of  a body when it is taken 32 km below the surface of the earth? [Radius of the earth=6400km]
  • 1%
  • 0.75 %
  • 0.5 %
  • 0.25 %
The value of $$'g'$$ at a depth of $$80 km$$ will be (Radius of earth $$= 6400 km$$ and value of $$'g'$$ on the surface of earth is $$10m/s^2$$)
  • $$990 \ cm/s^2$$
  • $$980 \ cm/s^2$$
  • $$970 \ cm/s^2$$
  • $$1000 \ cm/s^2$$
The weight of an astronaut in outer space is
  • Less than his actual weight
  • more than his actual weight
  • same as his actual weight
  • zero
If the distance between the earth and sun were to be doubled from its present value, the number of days in a year would be :
  • 64.5
  • 1032
  • 182.5
  • 730
0:0:1


Answered Not Answered Not Visited Correct : 0 Incorrect : 0

Practice Class 11 Engineering Physics Quiz Questions and Answers