In freely falling system, if potential energy is equal to kinetic energy. Then force of friction of air will
Correct answer: C. Be zero
- A. Be negligible
- B. Be maximum
- C. Be zero
- D. Not be predicted
Explanation
If mgh = ½ m v² without additional terms, no energy is lost to friction; thus frictional work fh = 0, implying negligible or zero air friction. So option C.
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Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
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