Solution:
Let plank moves x distance in opposite direction. Then, displacement of man relative to ground will be (L x). Applying law of conservation of momentum,
or
Solving this equation, we get
Displacement of man relative to ground
A man of mass M stands at one end of a plank of length L which lies at rest on a frictionless surface.
The man walks to the other end of the plank. If the mass of the plank is the distance that the man
moves relative to the ground is
Let plank moves x distance in opposite direction. Then, displacement of man relative to ground will be (L x). Applying law of conservation of momentum,
or
Solving this equation, we get
Displacement of man relative to ground