1 joule is equal to how many ergs? MCQ with Answer and Explanation

1 joule is equal to how many ergs?
A. 10⁶
B. 10⁷
C. 10⁵
D. 10⁸
Answer: Option B
Solution (By JKSSB Mock Tests)
1 J = 1 kg m²/s². In CGS, 1 kg = 10³ g, 1 m = 10² cm => 1 J = (10³ g) × (10² cm)² / s² = 10⁷ g cm²/s² = 10⁷ erg. Key conversion.

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