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A conductor carries a steady current when a charge of 30 C passes through a given cross-section in 1.5 minutes. The current in the conductor is
A0.20 A
B0.33 A
C20 A
D45 A
Answer & Solution
Correct answer: B. 0.33 A
1. For a steady current, $I = q/t$.
2. Convert time: $t = 1.5 \times 60 = 90\ \text{s}$.
3. $I = 30/90 = 0.33\ \text{A}$.
4. Option C (20 A) wrongly uses $t = 1.5\ \text{s}$; A divides further incorrectly.
_Source: NCERT Class 12 Physics Ch 3 "Current Electricity", p.1_
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