Explanation:
study of social sciencake us an effcient citizen of a democracy ,and it also help us to solve the practical problem in our daily life.
Answer:
a)
, b) 
Explanation:
a) The acceleration due to gravity inside the planet is:





b) The acceleration at the surface of the planet is:

Explanation:
It is given that,
Electric field, 
We need to find the change in the electric potential energy of the proton-field system when the proton travels to x = 2.5 m
From the conservation of energy, the loss in potential energy is equal to the gain in kinetic energy and kinetic energy is is equal to the work done.




So, the change in electric potential energy of the proton field system is
. Hence, this is the required solution.