Question

Two cars are traveling towards one another. The VW Bug has a mass of 187 kg and its initial velocity is -38 m/s. The compact car has a mass of 702 kg and an initial velocity of 23 m/s. They collide and stick together. How fast does the wreckage move immediately after the collision

Answer 1

10.17 m/s in the direction the compact car was going (+)

Step-by-step explanation:

Law of conservation of momentum states that total P before the collision must equal total momentum after the collision.

P = mv

solve for v, velocity of the two cars stuck together after the collision:

(187kg)(-38 m/s) + (702kg)(23 m/s) = (187 + 702 kg)v

momentum before = momentum after

-7106 kg·m/s + 16146 kg·m/s = 889 kg(v)

9040 kg·m/s = 889 kg(v)

v = 9040 kg·m/s / 889 kg = 10.17 m/s