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The current in a conductor is expressed as I = 3t2 + 4t3, where I is in Ampere and t is in second. The amount of electric charge that flows through a section of the conductor during t = 1 s to t = 2 s is C.
22
q = 12 I dt = 12 (3t2 + 4t3 )dt
= [t3 + t4 ]12 = (8 + 16) - (1 + 1)
= 22 C
Answer: 22
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