Question

A 1200 kg car traveling north at 10 m/s is rear-ended by a 2000 kg truck traveling at 30 m/s. What is the total momentum before and after the collision?

Answer 1

The total momentum before and after collision is 72000 kg-m/s.

Step-by-step explanation:

Given that,

Mass of car = 1200 kg

Velocity of car = 10 m/s

Mass of truck = 2000 kg

Velocity of truck = 30 m/s

Using conservation of momentum

The total momentum before the collision is equal to the total momentum after collision.

`m_(1)v_(1)+m_(2)v_(2)=(m_(1)+m_(2))V`

Where,
`m_(1)`=mass of car

`v_(1)` =velocity of car

`m_(1)`=mass of truck

`v_(1)` =velocity of truck

Put the value into the formula

`1200*10+2000*30=(1200+2000)V`

`V=(1200*10+2000*30)/((1200+2000))`

`V = 22.5\ m/s`

Now, The total momentum before collision is

`P=m_(1)v_(1)+m_(2)v_(2)`

`P=1200*10+2000*30`

`P=72000\ kg-m/s`

The total momentum after collision is

`P=(m_(1)+m_(2))v_(2)`

`P=(1200+2000)*22.5`

`P= 72000 kg-m/s`

Hence, The total momentum before and after collision is 72000 kg-m/s.