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प्रश्न
What are the S.I. and C.G.S units of work? How are they related? Establish the relationship.
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उत्तर
S.I unit of work is Joule.
C.G.S unit of work is erg.
Relation between joule and erg:
1 joule = 1 N × 1 m
But 1 N = 105 dyne
And 1 m = 100 cm = 102 cm
Hence, 1 joule = 105 dyne × 102 cm
= 107 dyne × cm = 107 erg
Thus, 1 Joule = 107 erg
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