Answer:
5 m/s, moving to the South.
Explanation:
Parameters given:
Mass of car, m = 1500 kg
Initial velocity of car, u = 15 m/s
Mass of truck, M = 4500 kg
Initial velocity of truck, v = 0 m/s (Truck is at rest)
Final velocity of car, U = 0 m/s (Car comes to a stop)
Final velocity of truck = V
Because the collision is elastic, we can apply the principle of conservation of momentum, we have that:
Total initial momentum = Total final momentum
m*u + M*U = m*v + M*V
(1500 * 15) + (4500 * 0) = (1500 * 0) + (4500 * V)
22500 + 0 = 0 + 00V
=> V = 22500/4500
V = 5 m/s
The velocity carries a positive sign, hence, it's moving in the same direction as the car was moving initially.
That is, it's moving to the South.