Gravitation - Result Question 10

10. Two spherical bodies of mass M and 5M and radii R and 2R 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

(a) 4.5R

(b) 7.5R

(c) 1.5R

(d) 2.5R

[2015]

Show Answer

Answer:

Correct Answer: 10. (b)

Solution:

  1. (b) Let the distance moved by spherical body of mass M is x1 and by spherical body of mass 5m is x2

Before collision At the time of collision

As their C.M. will remain stationary

So, (M)(x1)=(5M)(x2) or, x1=5x2

x1+x2=9R

So, x1=7.5R



NCERT Chapter Video Solution

Dual Pane