Answer: I2R.
- A IR
- B I2R
- C IR2
- D I2/R
Correct answer: B. I2R
Explanation: P = I2 R = V2/R = IV. All three forms are equivalent. P = I2 R is most direct.
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.