A boy of mass 50 kg is standing at one end of a, boat of length 9 m and mass 400 kg. He runs to the other, end. The distance through which the centre of mass of the boat boy system moves is
- 0
1 m
2 m
3 m
The Correct Option is A
Solution and Explanation
No external force is exerted on the boat, thus the boat experiences no external force.
The main force involved in this process is the frictional force between the boy and the surface of the boat.
So, we can say that the position of the center of mass will remain constant, indicating zero displacement of the center of mass.
Given that there are no external forces acting on the boat-boy system, and the center of mass was initially stationary, it will continue to remain at rest.
Therefore, the displacement of the center of mass equals 0 meter.
So, the correct option is (A): 0
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Concepts Used:
Center of Mass
The center of mass of a body or system of a particle is defined as a point where the whole of the mass of the body or all the masses of a set of particles appeared to be concentrated.
The formula for the Centre of Mass:
Center of Gravity
The imaginary point through which on an object or a system, the force of Gravity is acted upon is known as the Centre of Gravity of that system. Usually, it is assumed while doing mechanical problems that the gravitational field is uniform which means that the Centre of Gravity and the Centre of Mass is at the same position.