The work energy theorem states that the net work done on a body equals
Correct answer: B. the change in its kinetic energy
- A. its total energy
- B. the change in its kinetic energy
- C. the change in its potential energy
- D. the power delivered to it
Explanation
Positive net work speeds the body up and negative net work, as from friction, slows it down, and the theorem holds whatever forces are involved. It is often the quickest route to a final speed when the force varies or the path is complicated. Changes in potential energy are accounted for by the work done against conservative forces such as gravity.
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About Work-Energy Theorem
The work-energy theorem states that the net work done on an object equals its change in kinetic energy. Questions involve positive and negative work, variable forces and force-displacement graphs, acceleration or deceleration, and the difference between this theorem and conservation of mechanical energy, which also requires attention to potential energy and non-conservative work.
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