i=20t+8t2
i=dtdq⇒∫dq=∫idt
⇒q=∫015(20t+8t2)dt
q=(220t2+38t3)015
q=10×(15)2+38(15)3
q=2250+9000
q=11250C
JEE Main 2021 — Physics Electromagnetism
A current through a wire depends on time as i=α0t+βt2, where α0=20As−1 and β=8As−2. Find the charge crossed through a section of the wire in 15s.
Held on 24 Feb 2021 · Verified 6 Jul 2026.
2250C
11250C
2100C
260C
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