According to the work-energy theorem, if the net work done on an object is zero, then its kinetic energy ________.
Remains unchanged
The work-energy theorem states that the net work done on a body equals the change in its kinetic energy: \(W_{net} = \Delta KE = KE_f - KE_i\).
If \(W_{net} = 0\), then \(KE_f - KE_i = 0\), so \(KE_f = KE_i\).
The kinetic energy therefore neither rises nor falls; it stays the same. A body moving in a horizontal circle at constant speed is a classic case: the centripetal force is perpendicular to velocity, does zero work, and speed (and hence KE) is unchanged.
Hence, the kinetic energy remains unchanged.
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- During energy transformation, the total energy of a system:
- An object of mass 1 kg is moving with a velocity 10 m/s. Find the kinetic energy of the object.
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