Q.

Four identical particles of mass m are kept at the four corners of a square. If the gravitational force exerted on one of the masses by the other masses is (22+132)Gm2L2, the length of the sides of the square is    [2024]

1 2 L  
2 4 L  
3 3 L  
4 L/2  

Ans.

(2)

Fnet=2F+F'

F=Gm2a2 and F'=Gm2(2a)2

Fnet=2Gm2a2+Gm22a2

(22+132)Gm2L2=Gm2a2(22+12)a=4L