1. 
The ratio of the time periods for two satellites of equal mass in circular orbits of radii R and 4 R is 




2. 
A reference frame attached to the Earth 




3. 
Two planets of radii R_{1} and R_{2} have the same density. The ratio of their accelerations due to gravity at the surface is 




4. 
If the radius of the Earth were increased by a factor of 5 and its mass remained the same, then the acceleration due to gravity on the Earth would 




5. 
If the value of gravitational acceleration at a height h above the Earth's surface is the same as that at a depth d below the Earth's surface (with both h and d small compared to the Earth's radius R), then 



