Title 9. RC Circuits.pdf ✅

Capacitor stores charge, as a result voltage appears across it. The amount of charge and the voltage that appears across it is given by the formula , where is the capacitance of the capacitor which referes to the capacitor's ability to store charge. The more the charge the capacitance has in its store, the greater the voltage will be across it. Charging a capacitor When a capacitor is connected to a network, and the Thevenin voltage of the network is greater than the voltage across the capacitor, current will flow into the capacitor. The capacitor will start charging (storing charge) and its voltage will start increasing increasing) until it is equal to the Thevenin equivalent voltage, after which the charging will stop and there will be no current; then it will behave like an open-circuit. ( Discharging a capacitor When a capacitor is connected to a network, and the Thevenin voltage of the network is smaller than the voltage across the capacitor, current will flow out of the capacitor. The capacitor will start discharging (losing stored charge) and its voltage will start decreasing decreasing) until it is equal to the Thevenin equivalent voltage, after which the charging will stop and there will be no current; then it will behave like an open-circuit. ( Stage Charging Discharging Initially less than more than Transient increases towards [ decreases towards [ Steady-state 9.1 Capacitor theory Monday, May 12, 2025 3:55 AM 9. RC Circuits Page 1
The switch was kept at position A for a long period of time. After wise, it was moved to position B at t=0. Find voltage across the capacitor when t=10s. Draw a voltage time graph and mark your point on the graph. 9.2 Capacitor math - two stages Wednesday, May 7, 2025 11:27 AM 9. RC Circuits Page 2
The switch was at position 'a' for a long period of time. It was switched to position 'b' at t=0. And it stayed at 'b' for 2s, and then it was to position 'c'. Find the voltage at t=5s 9.3 Capcitor math - three stages Wednesday, May 7, 2025 11:27 AM 9. RC Circuits Page 3