HOW TO SOLVE A CIRCUIT CONTAINING A CAPACITOR ACROSS A RESISTOR?

To solve a circuit containing a capacitor across a resistor, you will need to use the principles of capacitance, resistance, and the properties of AC circuits. Here is a step-by-step process to solve the circuit:

1. Identify the circuit components: Determine the values of the resistor (R) and the capacitor (C) in the circuit. These values are usually given in the problem statement or can be measured using appropriate instruments.

2. Determine the input voltage: Find the value of the input voltage or acquire it from the problem statement. This information is crucial to solving the circuit.

3. Analyze the circuit using AC principles: If the circuit contains an alternating current (AC) source, convert it to the phasor representation. A phasor is a vector that represents the magnitude and phase of an AC quantity. This conversion simplifies AC circuit analysis.

4. Calculate the reactance of the capacitor: The reactance of a capacitor (Xc) is its opposition to changes in voltage and is dependent on the frequency of the AC signal. Use the following formula to calculate Xc: Xc = 1 / (2πfC), where f is the frequency of the AC signal and C is the capacitance value.

5. Calculate the impedance of the circuit: Impedance (Z) is the effective resistance of the circuit to the flow of AC current. In a circuit with a capacitor and resistor in series, the impedance is given by the formula Z = √(R^2 + Xc^2), where R is the resistance and Xc is the reactance of the capacitor.

6. Determine the current flowing through the circuit: Use Ohm's Law (I = V/Z) to calculate the current (I) flowing through the circuit, where V is the input voltage and Z is the impedance.

7. Calculate the voltage across the resistor and capacitor: The voltage drop across the resistor (VR) is given by VR = I * R, and the voltage across the capacitor (VC) is given by VC = I * Xc.

8. Determine the phase angles: Find the phase angle between the current and the voltage for both the resistor and capacitor. These phase angles indicate the time shift between the current and voltage waveforms.

By following these steps, you should be able to solve a circuit containing a capacitor across a resistor. Remember to pay attention to the units used and perform the calculations accurately to obtain the correct results.