Question

A car with mass m = 1.20x10³ kg is initially traveling directly east with a speed vi = 25.0 m/s. It crashes into the rear end of a truck with mass m = 9.00x10³ kg moving in the same direction with speed 20.0 m/s. Immediately after the collision, the car has a speed vf = 18.0 m/s in its original direction. What is the velocity of the truck immediately after the collision?

Answer 1

The velocity of the truck immediately after the collision is 14.0 m/s, in its original direction.

Step-by-step explanation:

To find the velocity of the truck immediately after the collision, we can use the principle of conservation of momentum. According to this principle, the total momentum before the collision is equal to the total momentum after the collision.

Before the collision, the momentum of the car is given by p1 = m1 * v1 and the momentum of the truck is given by p2 = m2 * v2. After the collision, the momentum of the car is given by p1' = m1 * v1' and the momentum of the truck is given by p2' = m2 * v2'.

Since the car and the truck are moving in the same direction, we can write the conservation of momentum equation as: m1 * v1 + m2 * v2 = m1 * v1' + m2 * v2'. Substituting the given values, we have (1.2x10^3 kg)(25.0 m/s) + (9.0x10^3 kg)(20.0 m/s) = (1.2x10^3 kg)(18.0 m/s) + (9.0x10^3 kg)(v2'). Solving for v2', we find that the velocity of the truck immediately after the collision is 14.0 m/s in its original direction.