The figure below shows a circuit with a battery and 3 resistors. The resistors h

Question

The figure below shows a circuit with a battery and 3 resistors. The resistors have values of 4 Ohm, 3 Ohm and 6 Ohm as shown. The battery is 18V. Calculate the equivalent resistance of the combination of resistors, the current through each resistor, and the voltage across each resistor.. If the resistors are replaced by capacitors with values of4 mu F, 3 mu F, and 6 mu F. calculate the equivalent capacitance of this new circuit, the charge on each capacitor, and the total energy stored in this circuit.

Explanation / Answer

A) Equivalent resistance of the circuit = 3||6 + 4 = 2 + 4 = 6 Ohms
Current in the circuit = 18/6 = 3A
so current through the 4 Ohms resistor = 3A
Potential drop across 4 Ohms resistor = 3*4 = 12V

Potential drop across the other 2 resistance in parallel = 18-12 = 6 V
so Current through 3 Ohms resistor = 2 A
and current through 6 Ohms resistor = 6/6 = 1 A

B) When they are replaced by capacitors
Equivalent capacitance = (6+3)||4 = 36/13 F

Total charge from the battery = 36/13 * 18 = 49.846 C

Charge stored in the 4 F capacitor = 49.846 F

Potential drop across the 4F capacitor = 12.461 V

Potential drop across the other set of capacitors = 18-12.461 = 5.538 V

Charge on 3F = 5.538 * 3 = 16.615 C

Charge on 6 F capacitor = 33.228 C

Total energy stored = .5*6*5.538^2 + .5*3*5.538^2 + .5*4*12.461^2 = 448.565 J

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.