Question

A car of mass 1200 kg, moving with a speed of 72 mph on a highway,

passes a small SUV with a mass 1 1/2 times bigger, moving at 2/3 the speed
of the car.
a) What is the ratio of the momentum of the SUV to that of the car?
b) What is the ratio of the KE of the SUV to that of the car?

Answer 1

momentum(p) = mass(m) x velocity(v)

KE = kinetic energy = 1/2 mv²

a.

the ratio of the momentum of the SUV to that of the car

`\tt (mv)/(1.5m(2)/(3)v )=1:1`

b. the ratio of the KE of the SUV to that of the car

`\tt (1/2* mv^2)/(1/2* 1.5m* ((2)/(3)v )^2)=(mv^2)/(1.5m(4)/(6)v^2 )=1:1`