GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the current in the circuit increases linearly with time
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the current in the circuit decreases linearly with time
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the current in the circuit increases exponentially with time
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the current in the circuit decreases exponentially with time
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Detailed explanation-1: -The current through the resistor decreases exponentially with time following the equation, i(t)=i0e−t/RC i ( t ) = i 0 e − t / R C, where i0 is the initial current, R is the resistance, and C is the capacitance.
Detailed explanation-2: -If a resistor is connected in series with the capacitor forming an RC circuit, the capacitor will charge up gradually through the resistor until the voltage across it reaches that of the supply voltage. The time required for the capacitor to be fully charge is equivalent to about 5 time constants or 5T.
Detailed explanation-3: -As the capacitor charges, its voltage rises toward the supply voltage, so the voltage difference decreases, and the charging current decreases.
Detailed explanation-4: -The voltage, current, and charge all decay exponentially during the capacitor discharge.