MCQ
A man sets his watch by a whistle that is $2\, km$ away. How much will his watch be in error. (speed of sound in air $330\, m/sec$)
  • A
    $3$ seconds fast
  • B
    $3$ seconds slow
  • C
    $6$ seconds fast
  • $6$ seconds slow

Answer

Correct option: D.
$6$ seconds slow
d
(d) Time lost in covering the distance of $2\, km$ by the sound waves

$t = \frac{d}{v} = \frac{{2000}}{{330}} = 6.06\,sec \approx 6\, sec$

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