pmontone said:Homework Statement
Voltage across 0.2-F cap is given by
v(t)=4(1-Є^(-10t)) for t>0
determine expression for the current i(t)
Homework Equations
i(t)=c (dv(t))/dt
The Attempt at a Solution
I'm really not sure were to begin with this problem what is the Є symbol and how do you take the derivative of it?
Voltage across a capacitor is the potential difference between the two plates of the capacitor. It is measured in volts (V) and represents the amount of electric potential energy stored in the capacitor.
The voltage across a capacitor is directly proportional to its capacitance and the amount of charge stored on the plates. This relationship is described by the equation V = Q/C, where V is voltage, Q is charge, and C is capacitance.
When a capacitor is connected to a circuit, the voltage across it initially increases as it charges up. Once it reaches its maximum voltage, the capacitor acts as an open circuit and no current flows through it. The voltage across the capacitor remains constant unless it is connected to a different voltage source or discharges through a resistor.
In an RC circuit, the voltage across a capacitor follows an exponential decay curve as it charges and discharges. Initially, the voltage across the capacitor increases rapidly, but as it approaches its maximum value, it takes longer for the voltage to change. The time constant, determined by the resistance and capacitance in the circuit, determines the rate of change of the voltage across the capacitor.
Yes, the voltage across a capacitor can be negative if it is connected in a circuit with a voltage source that is opposite in polarity to the initial charge on the capacitor. This can occur in circuits with alternating current or when a charged capacitor is connected to a circuit with a lower voltage source.