4. If there is more than one emf source in a complex circuit, Kirchhoff\'s Loop

Question

4. If there is more than one emf source in a complex circuit, Kirchhoff's Loop Rule says: V Ri If the path chosen around loop passes through an emf source from the negative terminal to the positive, it's a potential rise in the equation. If the path passes through from positive to L V1 5.3 negative, it's a potential drop. R3 2 Apply Kirchhoff's Rules to the circuit in Figure 8 and determine the individual currents and voltages in the resistors. Assume the emf sources have no internal resistance. Figur Vi = 5.30 V = 3.95 V R, 79.2 R2 = 121 R3 = 66.352

Explanation / Answer

Using Kirchoff's current rule :

V1 = I1*(R1) + (I1 - I2)*R2

So, 5.3 = I1*(79.2) + ( I1 - I2)*121 ---------- (1)

Similalrly,

V2 = I2*(R3) + (I2 - I1)*R2

So, 3.95 = I2*66.3 + (I2 - I1)*121 ---------- (2)

Solving the two equations simultaneously,

we get :

I1 = 0.064 A

I2 = 0.063 A

So, current through R1 = I1 = 0.064 A <------- answer

voltage across R1 = I1*R1 = 0.064*79.2 = 5.1 V <---------- answer

current through R2 = (I1 - I2) = 0.001 A <--------- answer

Voltage through R2 = 0.001*121 = 0.121 V <------ answer

Current through R3 = I2 = 0.063 A <------ answer

Voltage through R3 = I2*R3 = 0.063*66.3 = 4.2 V <----- answer

Related Questions

Navigate

• Browse (All)
• Browse 4
• Subjects

---

---

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