NEIEP Mechanics Practice Exam

What is the maximum length of lights you can install in a hoist way using 100 watt bulbs before tripping a 20A circuit?

1. 120 feet

2. 144 feet

3. 180 feet

4. 200 feet

The correct answer is: 144 feet

To determine the maximum length of lights using 100-watt bulbs that can be installed in a hoist way without tripping a 20A circuit, it's important to first understand the power consumption of the bulbs and the capacity of the circuit. A 100-watt bulb draws 100 watts of power. To find out how much total wattage can be safely used without exceeding the circuit's capacity, you can multiply the voltage of the circuit (typically 120 volts in most residential and commercial settings) by the amperage rating (20 amps in this case). So, the maximum power capacity of a 20A circuit at 120 volts is: Power (Watts) = Voltage (Volts) x Current (Amps) Power = 120V x 20A = 2400 Watts Next, to find out how many 100-watt bulbs you can install without exceeding this limit, you divide the total wattage the circuit can handle by the wattage of each bulb: 2400 Watts / 100 Watts per bulb = 24 bulbs Now, if we want to determine the maximum total length of lights you can install, we need to know how far apart the bulbs are spaced. Assuming a common spacing of