FIGURE 21-4
-A 100 V DC signal is applied to four resistors as shown in Figure 21-4. The values of the resistors are 20 Ω, 40 Ω, 60 Ω, and 80 Ω. What is the voltage across the 40 Ω resistor?
A) 20 V
B) 40 V
C) 60 V
D) 80 V
E) 100 V

Question

FIGURE 21-4 
-A 100 V DC signal is applied to four resistors as shown in Figure 21-4. The values of the resistors are 20 Ω, 40 Ω, 60 Ω, and 80 Ω. What is the voltage across the 40 Ω resistor?
A) 20 V 
B) 40 V 
C) 60 V 
D) 80 V 
E) 100 V

Quizplus · Accepted Answer

The resistors are in series, so the same current flows through each. The total resistance is 200 Ω (20+40+60+80). The current is 100 V / 200 Ω = 0.5 A. The voltage across the 40 Ω resistor is 0.5 A * 40 Ω = 20 V.

FIGURE 21-4 -A 100 V DC Signal Is Applied to Four Resistors