ARRL Technician Practice Exam

What is the current flow in a circuit with an applied voltage of 120 volts and resistance of 80 ohms?

1. 1.0 amperes

2. 1.5 amperes

3. 2.0 amperes

4. 2.5 amperes

The correct answer is: 1.5 amperes

To determine the current flow in a circuit when given an applied voltage and resistance, Ohm's Law can be applied. Ohm's Law states that the current (I) in amperes is equal to the voltage (V) in volts divided by the resistance (R) in ohms: \[ I = \frac{V}{R} \] In this case, with an applied voltage of 120 volts and a resistance of 80 ohms, the calculation would be as follows: \[ I = \frac{120 \text{ volts}}{80 \text{ ohms}} \] Performing the division results in: \[ I = 1.5 \text{ amperes} \] This correctly indicates that the current flowing through the circuit is 1.5 amperes. This approach is grounded in basic electrical principles, and by understanding the relationship between voltage, current, and resistance, one can easily ascertain the current in any given circuit scenario using Ohm's Law.