An amplifier booster that draws 20 amps is wired in parallel to the stereo system circuit on a vehicle. This will:

• A. increase the total current of the circuit by 20 amps
• B. cause a voltage drop across the motor
• C. not affect the total current
• D. decrease total current

Answer: (A)

When loads are wired in parallel, each device draws current independently from the same supply, and the total current the system must provide is the sum of the currents in all branches. If an amplifier booster draws 20 amps and is connected in parallel to the stereo circuit, the power source must supply the stereo’s current plus that additional 20 amps. So the overall current drawn from the circuit increases by 20 amps. The voltage across each parallel branch stays the same (assuming the vehicle’s electrical system maintains voltage). This explains why the total current rises with the added load, rather than staying the same or decreasing.