1. 
A reference frame attached to the Earth 




2. 
If a simple pendulum with a time period of 5 seconds is made to oscillate at a height R equal to the Earth's radius, then its time period at this height will be 




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. 
 The figure shows the elliptical orbit of a planet with the Sun at the focus. The areas of regions 1 and 2 are the same. If the planet takes times t_{1} to go from one end to the other end of region 1 and t_{2} to go from one end to the other end of region 2, then what is the relationship between t_{1} and t_{2}?  




5. 
If the radius of the Earth were increased by a factor of 3 and its mass remained the same, then the acceleration due to gravity on the Earth would 



