- A 9,300 kg. railroad car traveling at a velocity of 15m/s strikes a second boxcar at rest. If the two cars stick together and move off with a velocity of 6m/s, what is the mass
of the second car?

13950kg

Explanation:

If we make the system both railroad cars, we know that the momentum of the whole system doesn't change because the forces are internal.

Let a be the mass of the second car.

The original momentum is 9300*15 kg*m/s+ a*0 kg*m/s = 139500 kg*m/s

After sticking together, the momentum is (9300+a)kg*6m/s, which should be equal to 139500 kg*m/s

Therefore (9300+a)*6 = 139500

9300+a = 23250

a = 13950 kg

not moving. pos accel,

report!

explanation:

physics means: "the branch of science concerned with the nature and properties of matter and energy. the subject matter of physics, distinguished from that of chemistry and biology, includes mechanics, heat, light and other radiation, sound, electricity, magnetism, and the structure of atoms."