JEE Mains · Physics · STD 12 - 3. current electricity
The electric current through a wire varies with time as \(I=I_0+\beta t\). where \(I_0=20 \mathrm{~A}\) and \(\beta=3 \mathrm{~A} / \mathrm{s}\). The amount of electric charge crossed through a section of the wire in \(20 \mathrm{~s}\) is :
- A \(80\ \mathrm{C}\)
- B \(1000 \ \mathrm{C}\)
- C \(800 \ \mathrm{C}\)
- D \(1600 \ \mathrm{C}\)
Answer & Solution
Correct Answer
(B) \(1000 \ \mathrm{C}\)
Step-by-step Solution
Detailed explanation
Given that Current \(I=I_0+\beta t\) \( I_0=20 \mathrm{~A} \) \( \beta=3 \mathrm{~A} / \mathrm{s}\) \( \mathrm{I}=20+3 \mathrm{t} \) \( \frac{\mathrm{dq}}{\mathrm{dt}}=20+3 \mathrm{t} \) \( \int_0^q \mathrm{dq}=\int_0^{20}(20+3 \mathrm{t}) \mathrm{dt} \)…
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