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प्रश्न
Name and define the S.I. unit of time. How is it related to (i) minute (ii) hour, (iii) day, and (iv) year?
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उत्तर
The S.I. unit of time is second. In the short form, we write it as ‘ S ’.
One second is the time interval between the two consecutive ticks that you hear from the pendulum wall clock.
(i) 1 min = 60 s
(ii) 1 h = 60 min. = 3600 s.
(iii) 1 day = 24 h = 86400 s.
(iv) 1 year = 365 days = 3.15 × 107 s.
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