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Question
Express joule in terms of erg.
Solution
Relation between joule and erg :
1 joule = 1N × 1m
But 1N = 105 dyne and 1m =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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