The number of electrons in one coulomb charge is approximately MCQ with Answer and Explanation

The number of electrons in one coulomb charge is approximately
A. 9.1 × 10⁻³¹
B. 6.25 × 10¹⁸
C. 1.6 × 10⁻¹⁹
D. 6.25 × 10⁻¹⁹
Answer: Option B
Solution (By JKExamLibrary)
Charge of electron e = 1.6 × 10⁻¹⁹ C. Number n = 1/e = 1/(1.6×10⁻¹⁹) = 6.25 × 10¹⁸. This is a huge number. Important for current (1 A = 1 C/s).

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The time period of oscillation of a mass M attached to a spring of force constant k is:
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This question belongs to: Science Physics