Question

A 2kg cart collides with a 5kg cart. which car experiences the greater force.

1. the force is zero

2. the 2kg cart

3. the 5kg cart

4. the forces cancel out each other

5. the experience the same force

Answer 1

Both the carts will experience same force.

The concept used here is Newton's third law of motion which states that - "Every action has equal and opposite reaction".

So if we call force exerted by 2kg cart on 5kg cart an action force, then the force exerted by 5kg cart on 2kg cart will be reaction force. By Newtons third law, both the forces will be same.

In fact even if a fly collides with a train, they will exert equal and opposite forces on each other.

Note that these force do not cancel each other out as they are acting on two different objects!