CAT 1741

Sinclair Community College

1. A residential circuit has a voltage of 120 V and a current of 5 A. What is the circuit’s resistance? 24 Ω 600 Ω 25 Ω 0.042 Ω

Answer and explanation

24 Ω

Using Ohm’s Law, R = V ÷ I = 120 V ÷ 5 A = 24 Ω.

2. A residential circuit has multiple loads connected in parallel. What typically happens if one load is opened or fails? All loads automatically receive no voltage. Current stops through every load in the circuit. The other loads must operate only in series. The other loads can continue operating on their separate paths.

Answer and explanation

The other loads can continue operating on their separate paths.

Parallel circuits provide separate current paths for each load, so opening one path generally does not stop the other loads from operating.

3. What is the primary purpose of bonding conductive parts in a residential electrical system? To maintain an effective fault-current path and reduce dangerous voltage differences To connect the entire electrical system directly to earth To increase normal operating voltage across the circuit To prevent all current from flowing during a fault

Answer and explanation

To maintain an effective fault-current path and reduce dangerous voltage differences

Bonding joins conductive parts together so fault current has an effective path and hazardous voltage differences between those parts are reduced.

4. What is the primary function of a circuit breaker in a residential electrical system? Regulate normal current to a constant value Keep conductors energized during an overload Increase circuit voltage when demand rises Open the circuit when current exceeds its safe rated level

Answer and explanation

Open the circuit when current exceeds its safe rated level

A circuit breaker provides overcurrent protection by opening the circuit when current exceeds the safe level for the applicable conditions, helping prevent conductors from overheating.

5. A residential circuit operates at 120 volts and draws 5 amperes of current. What electrical power does it use? 24 watts 600 watts 625 watts 125 watts

Answer and explanation

600 watts

Electrical power is calculated as P = V × I. Therefore, 120 volts × 5 amperes = 600 watts.

Privacy · Academic integrity

Your privacy, your choice

Harbor uses optional analytics and advertising cookies only with your permission.

Cookie settings

Change these choices anytime.

NecessarySecurity, sessions, and saved privacy choices. AnalyticsHelps Harbor improve the product. AdvertisingMeasures campaigns and builds retargeting audiences.