Question

Assume that the acceleration due to gravity on the surface of the moon is $$0.2$$ times the acceleration due to gravity on the surface of the earth. If $${R_e}$$ is the maximum range of a projectile on the earth's surface, what is the maximum range on the surface of the moon for the same velocity of projection

A. $$0.2\,{R_e}$$
B. $$2\,{R_e}$$
C. $$0.5\,{R_e}$$
D. $$5\,{R_e}$$  
Answer :   $$5\,{R_e}$$
Solution :
Range of projectile $$R = \frac{{{u^2}\sin 2\theta }}{g}$$
if $$u$$ and $$\theta $$ are constant then $$R \propto \frac{1}{g}$$
$$\eqalign{ & \frac{{{R_m}}}{{{R_e}}} = \frac{{{g_e}}}{{{g_m}}} \Rightarrow \frac{{{R_m}}}{{{R_e}}} = \frac{1}{{0.2}} \cr & \Rightarrow {R_m} = \frac{{{R_e}}}{{0.2}} \Rightarrow {R_m} = 5{R_e} \cr} $$

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
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. $$\frac{1}{4}mgR$$
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. $$730$$
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. $$4 \,hr$$

Practice More Releted MCQ Question on
Gravitation


Practice More MCQ Question on Physics Section