FIGURE 21-5
-Three resistors of values 2 Ω, 6 Ω and 12 Ω are connected across a DC voltage source as shown in Figure 21-5. If the total current through the circuit is 2.0 A, what is the applied voltage?
A) 6.0 V
B) 3.0 V
C) 2.0 V
D) 2.7 V
E) 1.5 V

Question

FIGURE 21-5 
-Three resistors of values 2 Ω, 6 Ω and 12 Ω are connected across a DC voltage source as shown in Figure 21-5. If the total current through the circuit is 2.0 A, what is the applied voltage?
A) 6.0 V 
B) 3.0 V 
C) 2.0 V 
D) 2.7 V 
E) 1.5 V

Quizplus · Accepted Answer

To find the applied voltage, we can use Ohm's Law: V = IR. 
The total resistance of the circuit, RT, is the sum of the individual resistances: RT = 2 Ω + 6 Ω + 12 Ω = 20 Ω. 
Then, we can use Ohm's Law to find the voltage: V = IR = (2.0 A)(20 Ω) = 40 V. 
Therefore, the applied voltage is 40 V.

FIGURE 21-5 -Three Resistors of Values 2 Ω, 6 Ω and 12