Questions: Series Circuits

Question 1

Three resistors of 2 Ω, 3 Ω, and 5 Ω are connected in series. What is the total resistance?

• A. 10 Ω
• B. 0.97 Ω
• C. 3.33 Ω
• D. 30 Ω

Answer: (A)

In series, total resistance is the sum: R_total = 2 + 3 + 5 = 10 Ω.

Question 2

In a series circuit, the current through every component is the same.

• T. True
• F. False

Answer: True

There is only one path for current in a series circuit, so all charge must flow through every component. The current is identical everywhere in the loop.

Question 3

A 12 V battery is connected to two resistors in series: 3 Ω and 6 Ω. What is the voltage across the 6 Ω resistor?

Model answer: 8 V. Total resistance = 9 Ω, current = 12/9 = 4/3 A, voltage across 6 Ω = IR = (4/3)(6) = 8 V.

Find total R (3 + 6 = 9 Ω), then total I = V/R = 12/9 A. The voltage across the 6 Ω resistor is V = IR = (12/9)(6) = 8 V. The remaining 4 V is across the 3 Ω resistor.