Question

Two spherical bodies of mass $'m'$ and $5M$ and radii $R$ and $2R$ respectively are 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 just before collision is

• A. $2.5R$
• B. $4.5R$
• C. $7.5R$
• D. $1.5R$

Answer 1

Answer: (C)

$7.5R$

Answer 2

The two spheres collide when the smaller sphere covered the distance of $7.5\, R.$