Q 11 :    

Three identical spheres of mass m, are placed at the vertices of an equilateral triangle of length a. When released, they interact only through gravitational force and collide after a time T = 4 seconds. If the sides of the triangle are increased to length 2a and also the masses of the spheres are made 2m, then they will collide after ________ seconds.         [2025]



(8)

TmxGyaz

TMx[M1L3T2]y[L]z

TMxyL3y+zT2y

xy=0  x=y

2y=1  y=12, x=12

3y+z=0  z=3y=32

Hence, Tm1/2G1/2a3/2

T(a3m)1/2  T=4×(232)1/2=8 s