Question

The gravitational force between two masses kept at a certain distance is pN.The same two masses are now kept in water and the distance between them is same.If the gravitational force between these two masses in water is qN,then

Answer 1

Note that gravitational force only depends on the product of masses and distance between them.
It is independent of the surrounding medium . So ,
pN = qN
So , p=q

Answer 2

Answer:  

p = q

Solution:

The gravitational force is the attractive force exerted by an object on another object. It is ‘directly proportional’ to the ‘product of the masses of the objects’ and ‘inversely proportional’ to the ‘square of distance between the objects’.

Also from Newton’s second law it is known that any kind of force is directly proportional to the ‘mass of the object’ and the acceleration exerted by the object. So, the gravitational force is ‘independent of the medium’ in which the object is kept.

Thus, the ‘gravitational force’ between two masses in air will be equal to the ‘gravitational force’ between them in water provided the distance between the two masses is constant. So pN = qN.

Thus p is equal to q.