Question

the gravitational force between two object is 49 Newton how much distance between these objects be decreased so that the force between them becomes double?​

Answer 1

GmM / r2

100 = Gm M/ r2

r2= GmM/100

now for the second case

F' = GmM / r'250 = GmM / r'2

r'2= GmM / 50

or

r'2= 2 r2

thus,

r' = r√2