A three-cell flashlight has 3 batteries in series, each with an emf of 1.5 V. If the bulb has a resistance of 50 Ω, what current flows when the flashlight is operating? (Assume the internal resistance of the batteries is negligible.)
A) 30 mA
B) 10 mA
C) 27 mA
D) 90 mA
E) 11 A

Question

Quizplus · Accepted Answer

The total emf of the batteries in series is 3 * 1.5 V = 4.5 V. Using Ohm's Law (V = IR), the current I = V/R = 4.5 V / 50 Ω = 0.09 A or 90 mA.

A Three-Cell Flashlight Has 3 Batteries in Series, Each with an Emf