The correct answer to the question is : A) 400 N
EXPLANATION:
Let us consider two bodies having masses M and M' which are separated by a distance of R.
The gravitational force that acts between them is calculated as -
Gravitational force F = \(G\frac{MM'}{R^2}\)
Here, G is known as the universal gravitational force constant.
From above, we see that F is inversely proportional to the square of separation distance.
As per the question, the gravitational force between them F = 1600 N.
The distance between them is doubled.
Hence, the force between them will be reduced by four times as per the above relation.
Hence, the gravitation force will be = \(\frac{1600\ N}{4}\)
= 400 N. [ANS]
