Power in parallel circuits determines total current

Steps:

• Each lamp dissipates 0.60 W at 3 V, so total power for three lamps is 3 × 0.60 W = 1.80 W.
• In a parallel circuit with negligible internal resistance, the cell supplies the total power at 3 V.
• Total current I = total power / voltage = 1.80 W / 3 V = 0.60 A.

Why C is correct:

• The power formula P = I V shows total current equals total power divided by voltage for the entire circuit.

Why the others are wrong:

• A: 0.07 A miscalculates resistance or ignores multiple lamps.
• B: 0.20 A is current through one lamp only (0.60 W / 3 V), not total.
• D: 0.83 A likely errors in combining resistances or power addition.

Final answer: C