Answer: 2 ohm.
- A 2 ohm
- B 4 ohm
- C 8 ohm
- D 1 ohm
Correct answer: A. 2 ohm
Explanation: 1/R = 1/4 + 1/4 = 2/4. R = 2 ohm. For equal resistors in parallel: R/n = 4/2 = 2 ohm.
In series, the same current flows through both resistors; in parallel, the current splits between branches and the voltage across each resistor is the same.
Concept context
Ohm's law, resistors, Kirchhoff's laws, Wheatstone bridge, and cells.