Posted by Sarah on .
A 1200 kg car is moving on the freeway at 65 mph. (A) find the magnitude of its momentum and its kinetic energy in SI units. (b) if a 2400 kg SUV has the same speed asthe 1200 kg car, how much momentum and kinetic energy does it have?

Physics 
bobpursley,
on b), twice the mass means twice the momentum and twice the energy.
a) change 65mph to m/s. To check that, put this in your google search window:
65miles/hr in m/s 
Physics 
Sarah,
so the answer would be 29.05 m/s for a

Physics 
bobpursley,
No. That is the velocity. Now compute momentum, and KE.

Physics 
Camille,
300 000 = (1/2)M x 20^2 so M = 1 500kg