A car of mass 1411 kg collides head-on with a parked truck of mass 2000 kg.Spring mounted bumpers ensure that the collision is essentially elastic.If the velocity of the truck is 17 km/h (in the same direction as the car's initial velocity)after the collision,what is the initial speed of the car?

Question

Quizplus · Accepted Answer

Explanation:Momentum is conserved, so the total momentum before the collision is equal to the total momentum after the collision. The initial momentum of the car is 1411 kg * v, where v is the initial speed of the car. The initial momentum of the truck is 2000 kg * 0 = 0. The final momentum of the car is 1411 kg * (-17 km/h), where -17 km/h is the final speed of the car. The final momentum of the truck is 2000 kg * 17 km/h. Setting the initial momentum equal to the final momentum, we get:1411 kg * v + 0 = 1411 kg * (-17 km/h) + 2000 kg * 17 km/h1411 kg * v = 34000 kg*km/hv = 24.09 km/hTherefore, the initial speed of the car is 24.09 km/h, which is closest to 21 km/h.

A Car of Mass 1411 Kg Collides Head-On with a Parked