Lucy and Fran are driving monster trucks along the same straight line in opposite directions towards each other. The combined mass of Lucy and her truck is 5400 kg and the combined mass of Fran and her truck is 4700 kg. They collide directly. Immediately before the collision, Lucy’s truck is moving with speed and Fran’s truck is moving with speed . Immediately after the collision, Lucy and Fran’s monster trucks are moving at the same speed.
(i)
Given that Lucy and Fran’s monster trucks are moving in the same direction after the collision, find the speed at which they both travel.
(ii)
State which person’s direction of motion has been reversed.
(iii)
Calculate the change in momentum of Fran’s monster truck due to the collision.