Body accelerates from rest to 4 m/s, energy is E. If it accelerates from rest to 24, then energy is nE. Find n.
Solution and Explanation
The correct answer is 4.
\(E=\frac{1}{2}mu^2\)
\(nE=\frac{1}{2}m(24)^2=4E\)
⇒ n = 4
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Concepts Used:
Kinetic energy
Kinetic energy of an object is the measure of the work it does as a result of its motion. Kinetic energy is the type of energy that an object or particle has as a result of its movement. When an object is subjected to a net force, it accelerates and gains kinetic energy as a result. Kinetic energy is a property of a moving object or particle defined by both its mass and its velocity. Any combination of motions is possible, including translation (moving along a route from one spot to another), rotation around an axis, vibration, and any combination of motions.
