Power scales with square of current

Steps:

• Calculate original power: P = I²R = (0.2)² × 12 = 0.04 × 12 = 0.48 W.
• Double current to 0.4 A.
• New power: P' = (0.4)² × 12 = 0.16 × 12 = 1.92 W (1.9 W).
• Since P ∝ I², doubling I quadruples P: 0.48 × 4 = 1.92 W.

Why C is correct:

• Formula P = I²R shows power quadruples when current doubles for fixed R.

Why the others are wrong:

• A: Matches original power, ignores current change.
• B: Assumes power doubles with current, but it's I².
• D: Overestimates by factor of 10, perhaps misapplying V = IR.

Final answer: C