Question

Find the gravitational force of attraction between two bodies of 4 kg and 20 kg separated by 2 m distance in air. How will the force change if masses are now placed in water at same distance​

Answer 1

Answer:

Here, mass of body A,m1=2kg , mass of body B,m2=4kg

distance between the bodies A and B=2m

mass of body C,m=1kg

Let body C be placed at a distance x from A,

Thus, AC=x and BC=(2−x)

As gravitational force on C due to A = gravitational force on C due to B,

F1=F2

or Gm1mx2=Gm2m(2−x)2 or m1x2=m2(2−x)2

or 2x2=4(2−x)2or2x2=(2−x)2

Taking square root of both sides, we get 2–√x=2−x

or 1.414x+x=2orx=22.414=0.83m