Answer:
7 m/s
Explanation:
Find the total mass
m1+m2 = total mass
700kg+300kg = 1000kg
Find the velocity of each mass
v1 = 10m/s
v2 = 0m/s
Find the combined momentum
m1v1 + m2v2 = mfvf
(700)(10)+(300)(0)=(1000)(vf)
7000=1000(vf)
7=vf
So the velocity of the two cars rolling together is 7 m/s