COMEDK · Physics · 19. Current Electricity
Current in a conductor is expressed as \(I = 8t^3 + 3t^2 + 1\), where current I is measured in amperes and time t is measured in seconds. What is the charge that flows through a cross-section of the conductor between time t = 1s to t = 2s?
- A \(29\ \text{C}\)
- B \(38\ \text{C}\)
- C \(18\ \text{C}\)
- D \(49\ \text{C}\)
Answer & Solution
Correct Answer
(B) \(38\ \text{C}\)
Step-by-step Solution
Detailed explanation
The current in the conductor is given by \(I = \dfrac{dq}{dt} = 8t^3 + 3t^2 + 1\) The charge \(q\) that flows through a cross-section is the integral of current with respect to time. \(dq = I dt = (8t^3 + 3t^2 + 1) dt\) Integrating both sides from \(t = 1\) s to \(t = 2\) s:…
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