A uniform rope of length 4 m and mass 0.4kg is held on a frictionless table in such a way that 0.6m of the rope is hanging over the edge. The work done to pull the hanging part of the rope onto the table is, (Assuming g=10m/s2)
- 0.36J
- 0.24J
- 0.12J
- 0.18J
The Correct Option is D
Solution and Explanation
The work done in pulling the chain onto the table can be calculated using the equation: �=��ℎ(1−��)2=4×10×4×(103)2=72 JW=mgh(1−xL)2=4×10×4×(310)2=72J.
The answer, rounded to two decimal places, is 0.18 J.
The correct answer is option (D): 0.18J
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Concepts Used:
Laws of Motion
The laws of motion, which are the keystone of classical mechanics, are three statements that defined the relationships between the forces acting on a body and its motion. They were first disclosed by English physicist and mathematician Isaac Newton.
Newton’s First Law of Motion
Newton’s 1st law states that a body at rest or uniform motion will continue to be at rest or uniform motion until and unless a net external force acts on it.
Newton’s Second Law of Motion
Newton's 2nd law of motion deals with the relation between force and acceleration. According to the second law of motion, the acceleration of an object as built by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
Newton’s Third Law of Motion
Newton's 3rd law of motion states when a body applies a force on another body that there is an equal and opposite reaction for every action.