Questions: Parallel Circuits

Question 1

Two 6 Ω resistors are connected in parallel. What is the total resistance?

• A. 12 Ω
• B. 6 Ω
• C. 3 Ω
• D. 0.33 Ω

Answer: (C)

1/R_total = 1/6 + 1/6 = 2/6 = 1/3, so R_total = 3 Ω. Two equal resistors in parallel give half the resistance of one.

Question 2

In a parallel circuit, each branch receives the full battery voltage.

• T. True
• F. False

Answer: True

All branches in a parallel circuit are connected directly across the same two points (the battery terminals), so each branch experiences the full voltage.

Question 3

A 12 V battery is connected to two resistors in parallel: 4 Ω and 12 Ω. How much total current leaves the battery?

Model answer: 4 A. The 4 Ω branch draws 12/4 = 3 A, the 12 Ω branch draws 12/12 = 1 A, so total current = 3 + 1 = 4 A.

Each branch gets the full 12 V. Use I = V/R for each branch separately: 3 A + 1 A = 4 A total. (You can verify: R_total = 3 Ω, so I_total = 12/3 = 4 A.)