FIGURE 21-3
-A 4-Ω resistor is connected in parallel with a 12-Ω resistor and this combination is connected to a DC power supply with voltage V as shown in Figure 21-3. If the total current in this circuit is 2 A, what is the value of voltage V?
A) 2 V
B) 3 V
C) 6 V
D) 1.5 V
E) None of the other answers is correct.

Question

FIGURE 21-3 
-A 4-Ω resistor is connected in parallel with a 12-Ω resistor and this combination is connected to a DC power supply with voltage V as shown in Figure 21-3. If the total current in this circuit is 2 A, what is the value of voltage V?
A) 2 V 
B) 3 V 
C) 6 V 
D) 1.5 V 
E) None of the other answers is correct.

Quizplus · Accepted Answer

The equivalent resistance of the parallel combination of 4 Ω and 12 Ω resistors is 3 Ω. Using Ohm's Law, we have V = IR = (2 A)(3 Ω) = 6 V. Therefore, the answer is (C) 6 V.

FIGURE 21-3 -A 4-Ω Resistor Is Connected in Parallel with a 12-Ω