7. Problem to find the forces

 

The below figure represents two bodies of masses 20 \(kg\) and 15 \(kg\), moving with an initial velocity of 35 $m{s}^{-1}$ and 8 $m{s}^{-1}$ respectively. They collide with each other. After collision, they move with velocities 4 $m{s}^{-1}$ and 12 $m{s}^{-1}$ respectively. The time of collision is 2 \(s\).

 

 

Answer:

 

Force (\(F_1\)) \(=\)  \(N\)