Question

The first car, 300-kg car is moving at 20.0 m/s east and hits from behind a second car, 800-kg moving at 12.0m/s traveling aslo east. The two car are stuck and they move together after the colision. Find the final velocity of the two car.

Answer 1

Answer:

14.2 m/s

Explanation:

From reading the problem we know this is an inelastic collision since the objects stick together after the collision. We can write this as:

mv + MV = (m+M)x

Lets assign some values now:

m = 300 kg

M = 800 kg

v = 20 m/s

V = 12 m/s

x = Final Velocity (usually written as vf)

Now plug and chug!

(300)(20) + (800)(12) = (300+800)x

Simplify and isolate x (final velocity of both bodies):

6000 + 9600 = 1100x

15600 = 1100x

14.2 = x

14. 2 m/s = final velocity