The charge on a capacitor plate in a circuit, as a function of time, is shown in the figure
What is the value of current at $t = 4\,s$ ? ............... $\mu A$
A$0$
B$3$
C$2$
D$1.5$
JEE MAIN 2019, Easy
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A$0$
a Current $=$ slope of $q -t$ graph $= 0.$ [at $t = 4\,sec$ ]
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