1. Two trolleys, A and B, are on a smooth runway. Trolley A has a mass of $1.2\text{ kg}$ and is moving at $3.0\text{ m/s}$ towards trolley B. Trolley B has a mass of $0.80\text{ kg}$ and is stationary.

The trolleys collide and stick together.

Calculate the velocity of the two trolleys after the collision.

Use the equation:

$p=m\timesv$