Carriage 1 is moving forward at 15m/s and strikes carriage 2 which is stationary. After the collision both carriage move along together. Calculate the velocity of both carriages after the collision.

Momentum = mass x velocity

Before the collision

Carriage 1 = 1200kg x 15m/s = 18000 kg m/s

Carriage 2 = 1200kg x 0 m/s = 0 kg m/s

Total momentum before the collision = 18000 + 0 = 18000 kg m/s

Conservation of momentum states that the total momentum before a collision is equal to the total momentum after the collision.

Total momentum after the collision = 18000 kg m/s

Velocity = momentum/mass

Total mass of 2 carriages = 1200kg + 1200kg = 2400kg

Velocity = 18000/2400 = 7.5m/s

3. Use the image below to answer the following question