Question

A body of mass 80kg moving with a velocity of 6m/s hits a stationery body of mass 40kg. if the two bodies stick together after collision, calculate the magnitude of the velocity

​

Answer 1

Known :

m1 = 80 kg

v1 = 6 m/s

m2 = 40 kg

Solution :

p1 + p2 = p3

m1 • v1 + m2 • v2 = (m1 + m2) • v

Since body 2 is stationery before collision, then v2 = 0

m1 • v1 = (m1 + m2) • v

(80 kg)(6 m/s) = (80 kg + 40 kg) • v

v = 4 m/s