# Before a collision, CAR 1 has a mass of 1,200 kg and a velocity of 23 m/s due east and CAR 2 has a mass of 1,400 kg and a velocity of 28 m/s due west. If the two cars experience an completely inelastic collision, what is the final velocity of the two cars?

The final velocity of the two cars is 4.46 m/s due west.

## Expert Answers CAR 1, having a mass of 1,200 kg and traveling with a velocity of 23 m/s due east, has a completely inelastic collision with CAR 2, having a mass of 1,400 kg and a velocity of 28 m/s due west.

In a completely inelastic collision, the two objects undergoing collision are stuck together and, after the collision, move together at the same velocity. Only momentum is conserved in this collision.

The initial momentum of the two cars colliding together was

`M_0 = 1200*23 - 1400*28 `

If the two cars move at a velocity V after collision, the final momentum of the system is `M_1 = (1200+1400)*V`

As `M_0` and `M_1` are equal,

`1200*23 - 1400*28 = (1200+1400)*V`

`V = (1200*23 - 1400*28)/(1200+1400) = ~~-4.46 m/s`

Velocity due east has been considered positive, so the final velocity of the two cars is due west.

The final velocity of the two cars is 4.46 m/s due west.

Last Updated by eNotes Editorial on ## We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

• 30,000+ book summaries
• 20% study tools discount
• Ad-free content
• PDF downloads
• 300,000+ answers
• 5-star customer support