The charge flowing in a conductor varies with time as $Q = at -bt^2$. Then for current, which statement is incorrect.
$(A)$ decreases linearly with time
$(B)$ reaches a maximum and then decreases
$(C)$ fall to zero after time $t = a/2b$
$(D)$ changes at a rate $-2b$
Options :
A$A, B, C$
B$A, C, D$
C$B, C$
DOnly $B$
Medium
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DOnly $B$
d $(i)$ $\mathrm{I}=\frac{\text { da }}{\mathrm{dt}}=\mathrm{a}-2 \mathrm{bt}$ (linearly decreasing with time)
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