Here are the essential concepts you must grasp in order to answer the question correctly.
Work
Work is defined as the product of the force applied to an object and the distance over which that force is applied, in the direction of the force. Mathematically, it is expressed as W = F × d × cos(θ), where θ is the angle between the force and the direction of motion. In this context, calculating the work done by the hand involves determining the force exerted on the string and the distance it is pulled.
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Kinetic Energy
Kinetic energy is the energy possessed by an object due to its motion, calculated using the formula KE = 0.5 × m × v², where m is the mass and v is the velocity of the object. As the rotating mass gains speed due to the work done by the hand, its kinetic energy increases, which is essential for understanding the relationship between work and energy in this scenario.
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Newton's Second Law of Motion
Newton's Second Law states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass, expressed as F = m × a. This principle is crucial for analyzing how the force exerted by the hand affects the acceleration of the rotating mass, thereby influencing the work done and the resulting change in kinetic energy.
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