A 1000-kg car moving at 80 km/h collides head on with a 100-kg car moving west at 40km/h, and the two cars stick together. Which way does the wreckage move and with what initial speed?

Answer 1

Use conservation of momentum:

1000*80-100*40=1110(V)

solve for V. postive means East.

Answer 2

3.6 m/s^2