In a circuit, drift velocity of electrons is 10⁻⁴ m/s. Number density of free electrons is 10²⁹ /m³. Charge per electron 1.6 × 10⁻¹⁹ C. Cross-sectional area 10⁻⁶ m². Current is:
A1.6 A
B16 A
C0.16 A
D160 A
Answer & Solution
Correct answer: A. 1.6 A
I = nAvₑe = 10²⁹ × 10⁻⁶ × 10⁻⁴ × 1.6 × 10⁻¹⁹ = 1.6 × 10⁰ = 1.6 A. (Formula: I = nAeᵥ_d, where n = number density.)
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