Question

A 1120 kg car traveling initially with a speed of 27.40 m/s in an easterly direction crashes into the back of a 9 490 kg truck moving in the same direction at 20.0 m/s. The velocity of the car right after the collision is 18.0 m/s to the east. (a) What is the velocity of the truck right after the collision?

Answer 1

Answer:

41.5 m/s

Explanation:

Since there are no external forces, momentum must be conserved.

Momentum P = mv.

Total momentum before the collision:

$P = m_{car}v_{car} + m_{tru}_{ck}v_{tru}_{ck} = 1120 * 27.4 + 490 * 20 = 40.488$

Total momentum after the collision:

$P = 1120 * 18 + 490 * v_{tru}_{ck} = 40.488$

solving for v:

$v_{truck} = 41.5$