Question

Two objects of masses 50kg and 90kg, separated by a distance, exert a force of 3N on each other. What will be the gravitational force between them if
a) mass of one body is doubled?
b) mas of both bodies is halved
c) distanc of separation of bodies is doubled?

Answer 1

m1 = 50 kg
m2 = 90 kg

a) According to Newtons formula for gravitational force

F=(G M1×M2)/(R^2)

Where M1 and M2 are masses while R is the distance between the masses

So if we double mass of one body by keeping distance constant as

2M1 ×M2=2 M1×M2

So F =2(G×M1×M2)/(R^2)

Hence the gravitational force increases 2 times before if mass of one body is doubled by keeping R constant

b According to Newtons formula for gravitational force

F=(G M1×M2)/(R^2)

Where M1 and M2 are masses while R is the distance between the masses

So if we halved both masses by keeping distance constant as

(1/2)M1 ×(1/2)M2=(1/4)M1×M2

So F =(1/4)(G×M1×M2)/(R^2)

Hence the gravitational force increases (1/4) times before if both masses are halved by keeping R constant


c) The force of gravity between two objects will decrease as the distance between them increases. ... This means that if the distance is doubled, the gravitational force is decreased by a factor of 4. This is because the square of 2 is 2 x 2, which equals 4.