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Question
What are the S.I. and C.G.S units of work? How are they related? Establish the relationship.
Solution
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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