Question

A boat of mass 40 kg is at rest; A dog of mass 4 kg moves in the boat with a velocity of 10 m/s. what is the velocity of boat?
a) 4 m/s b) 2 m/s
c) 8 m/s d) 1 m/s

Answer 1

mv=(m+M)u
u=mv/(m+M) = 4•10/(4+40) = 0.9 m/s
d) 1 m/s

Answer 2

D) 1m/s