Question

A person weighing 60 kg in a small boat of mass 140 kg which is at rest , throws a 5 kg stone in the horizontal direction with a velocity of 14 m/s . The velocity of the boat immediately after the throw is ( in m/s)

Answer 1

Welcome Students,

◆ Answer -

Velocity of boat = -0.35 m/s

● Explanation -

Let mp, mb and ms be mass of the person boat and stone respectively.

# Given -

mp = 60 kg

mb = 140 kg

ms = 5 kg

vs = 14 m/s

# Solution -

Initial momentum of the system is -

pi = ms.us + (mp+mb).u

pi = 5×0 + (60+140)×0

pi = 0

Final momentum of the system will be -

pf = ms.vs + (mp+mb).v

pf = 5×14 + (60+140)×v

pf = 70 + 200v

By law of conservation of momentum,

pi = pf

0 = 70 + 200v

v = -70 / 200

v = -0.35 m/s

Therefore, velocity of the boat after throwing stone is 0.35 m/s in opposite direction.

Thanks dear ...

Answer 2

so friend this is answer