Question

Two spherical bodies of mass M and 5 M and radii R and 2 R released in free space with initial separation between their centres equal to 12 R. If they attract each other due to gravitational force only, then the distance covered by the smaller body before collision is [2015] (a) 4.5 R (b) 7.5 R (c) 1.5 R (d) 2.5 R

Answer 1

(B) 7.5 R.....

answer___

Answer 2

Explanation:

Distance between their surfaces =12R−R−2R=9R

a1/a2 = s1/s2

s1/s2= m /5m

s2 = 5s1

s1 +s2 = 9R

s  1 =1.5R

s  2 =7.5R