What is the maximum number of 50-W light bulbs you can connect in parallel in a 100-V home circuit without tripping the 40-A circuit breaker?
A) 20
B) 39
C) 79
D) 59
E) 58

Question

What is the maximum number of 50-W light bulbs you can connect in parallel in a 100-V home circuit without tripping the 40-A circuit breaker?
A) 20
B) 39
C) 79
D) 59
E) ​58

Quizplus · Accepted Answer

The total current drawn by the bulbs should not exceed 40 A. Each 50-W bulb at 100 V draws 0.5 A (Power = Voltage x Current, so Current = Power/Voltage = 50W/100V = 0.5A). Therefore, the maximum number of bulbs is 40 A / 0.5 A per bulb = 80 bulbs. However, to avoid tripping the breaker, you should use one less, which is 79 bulbs.

What Is the Maximum Number of 50-W Light Bulbs You