The charge flowing in a conductor changes with time as Q(t) = αt - βt² + γt³, where α, β and γ are constants. Minimum value of current is:
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The charge flowing in a conductor changes with time as Q(t) = αt − βt² + γt³, where α, β and γ are constants. Minimum value of current is:

G1 Physics · Accepted Answer

Current i = dQ/dt = α − 2βt + 3γt². For minimum current, di/dt = −2β + 6γt = 0, so t = β/(3γ). Substituting gives i(min) = α − β²/(3γ).