Question
Express joule in terms of erg.
✓
Answer
Relation between joule and erg:
1 joule $=1 N \times 1 m$
But $1 N=10^5$ dyne and $1 m=100 cm=10^2 cm$
Hence, 1 joule $=10^5$ dyne $\times 10^2 cm$
$= 10^7 dyne \times cm$
$= 10^7 erg$
Thus, $1$ Joule $= 10^7 $erg.
1 joule $=1 N \times 1 m$
But $1 N=10^5$ dyne and $1 m=100 cm=10^2 cm$
Hence, 1 joule $=10^5$ dyne $\times 10^2 cm$
$= 10^7 dyne \times cm$
$= 10^7 erg$
Thus, $1$ Joule $= 10^7 $erg.
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