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प्रश्न
Consider the motion of the tip of the minute hand of a clock. In one hour
(a) the displacement is zero
(b) the distance covered is zero
(c) the average speed is zero
(d) the average velocity is zero
उत्तर
(a) the displacement is zero
(d) the average velocity is zero
Displacement is zero because the initial and final positions are the same.
Average velocity = \[\frac{\text{ Displacement } }{\text{ Total time} } = 0\]
Distance covered = \[2\pi r\] ≠ 0
Average speed = \[\frac{\text { Distance travelled} }{\text{ Total time taken} } \neq 0\]
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