MHT CET20249 May 2024Evening ShiftPhysicsGravitationActual
A satellite is revolving around a planet in a circular orbit close to its surface. Let ' ' be the mean density and ' R ' be the radius of the planet. Then the period of the satellite is ( G = universal constant of gravitation)
Options
- A4 G
- BG
- C3 G
- D2 G
Correct answer
C. 3 G
Step-by-step solution
From Kepler's third law, aligned & T ^2= 4 ^2 r ^3 GM & ~T =2 r ^3 GM aligned As the satellite is very close to the planet, r=R . T =2 R ^3 GM ...(i) aligned & We know, Mass = Volume Density ( ) & = 4 3 R ^3 ...(ii) aligned Putting (ii) into (i) T=2 R^3 G 4 3 R^3 = 3 G