In an ideal pendulum oscillating without air resistance, which quantity remains constant?
AOnly kinetic energy
BOnly potential energy
CSum of kinetic and potential energies
DMomentum of the bob in a fixed direction
Answer & Solution
Correct answer: C. Sum of kinetic and potential energies
As the pendulum swings, kinetic energy and gravitational potential energy continuously convert into each other. In the absence of non-conservative forces, their sum, the mechanical energy, remains constant.
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