imagine a new planet having the same density as that of

Imagine a new planet having the same density as that of earth but it is $$3$$ times bigger than the earth in size. If the acceleration due to gravity on the surface of earth is $$g$$ and that on the surface of the new planet is $$g',$$ then

A. $$g' = \frac{g}{9}$$

B. $$g' = 27\,g$$

C. $$g' = 9\,g$$

D. $$g' = 3\,g$$

Answer : $$g' = 3\,g$$

Solution :
We know that
$$\eqalign{ & g = \frac{{GM}}{{{R^2}}} = \frac{{G\left( {\frac{4}{3}\pi {R^3}} \right)\rho }}{{{R^2}}} = \frac{4}{3}\pi GR\rho \cr & \frac{{g'}}{g} = \frac{{R'}}{R} = \frac{{3R}}{R} = 3 \cr & \therefore g' = 3\;g \cr} $$

Releted MCQ Question on
Basic Physics >> Gravitation

Releted Question 1

If the radius of the earth were to shrink by one percent, its mass remaining the same, the acceleration due to gravity on the earth’s surface would-

A. Decrease

B. Remain unchanged

C. Increase

D. Be zero

View Answer

Releted Question 2

If $$g$$ is the acceleration due to gravity on the earth’s surface, the gain in the potential energy of an object of mass $$m$$ raised from the surface of the earth to a height equal to the radius $$R$$ of the earth, is-

A. $$\frac{1}{2}\,mgR$$

B. $$2\,mgR$$

C. $$mgR$$

D. $$\frac{1}{4}mgR$$

View Answer

Releted Question 3

If the distance between the earth and the sun were half its present value, the number of days in a year would have been-

A. $$64.5$$

B. $$129$$

C. $$182.5$$

D. $$730$$

View Answer

Releted Question 4

A geo-stationary satellite orbits around the earth in a circular orbit of radius $$36,000 \,km.$$ Then, the time period of a spy satellite orbiting a few hundred km above the earth's surface $$\left( {{R_{earth}} = 6400\,km} \right)$$ will approximately be-

A. $$\frac{1}{2}\,hr$$

B. $$1 \,hr$$

C. $$2 \,hr$$

D. $$4 \,hr$$

View Answer

Imagine a new planet having the same density as that of earth but it is $$3$$ times bigger than the earth in size. If the acceleration due to gravity on the surface of earth is $$g$$ and that on the surface of the new planet is $$g',$$ then

Releted MCQ Question on
Basic Physics >> Gravitation

If the radius of the earth were to shrink by one percent, its mass remaining the same, the acceleration due to gravity on the earth’s surface would-

If $$g$$ is the acceleration due to gravity on the earth’s surface, the gain in the potential energy of an object of mass $$m$$ raised from the surface of the earth to a height equal to the radius $$R$$ of the earth, is-

If the distance between the earth and the sun were half its present value, the number of days in a year would have been-

A geo-stationary satellite orbits around the earth in a circular orbit of radius $$36,000 \,km.$$ Then, the time period of a spy satellite orbiting a few hundred km above the earth's surface $$\left( {{R_{earth}} = 6400\,km} \right)$$ will approximately be-

Practice More Releted MCQ Question on
Gravitation

Practice More MCQ Question on Physics Section

Imagine a new planet having the same density as that of earth but it is $$3$$ times bigger than the earth in size. If the acceleration due to gravity on the surface of earth is $$g$$ and that on the surface of the new planet is $$g',$$ then

Releted MCQ Question on Basic Physics >> Gravitation

If the radius of the earth were to shrink by one percent, its mass remaining the same, the acceleration due to gravity on the earth’s surface would-

If $$g$$ is the acceleration due to gravity on the earth’s surface, the gain in the potential energy of an object of mass $$m$$ raised from the surface of the earth to a height equal to the radius $$R$$ of the earth, is-

If the distance between the earth and the sun were half its present value, the number of days in a year would have been-

A geo-stationary satellite orbits around the earth in a circular orbit of radius $$36,000 \,km.$$ Then, the time period of a spy satellite orbiting a few hundred km above the earth's surface $$\left( {{R_{earth}} = 6400\,km} \right)$$ will approximately be-

Practice More Releted MCQ Question on Gravitation

Practice More MCQ Question on Physics Section

Releted MCQ Question on
Basic Physics >> Gravitation

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Gravitation