AP EAMCET202123 Aug 2021Evening ShiftPhysicsGravitationActual
The radius of Earth is about 6400 ~km and that of Mars is 3200 ~km , and mass of the Earth is about 10 times mass of Mars. An object weight 200 ~N on the surface of Earth. Then, its weight on the surface of Mars will be
Options
- A80 ~N
- B40 ~N
- C20 ~N
- D8 ~N
Correct answer
A. 80 ~N
Step-by-step solution
Given, radius of Earth and Mars are 6400 ~km and 3200 ~km , respectively. Mass of Earth =10 (Mass of Mars) M_e=10 M_m We know that, acceleration due to gravity at surface of a planet is g= G M R^2 , where, M= mass of planet and R= radius of planet. Taking the ratio of acceleration due to gravity of Mars to Earth, g_m g_e = G M_m R_m^2 G M_e R_e^2 = M_m M_e ( R_e R_m )^2 By substituting the values, we get aligned & g_m g_e = 1 10 ( 6400 3200 )^2= 1 10 4 & g_m= 2 5 g_e aligned Given, the weight on earth's surface, w_