What is the voltage across a 2-ohm resistor if a current of 0.5 amperes flows through it?

• A. 1 volt
• B. 0.5 volts
• C. 2 volts
• D. 4 volts

Answer: (A)

To find the voltage across a resistor, you can use Ohm's Law, which states that voltage (V) is equal to the current (I) flowing through the resistor multiplied by the resistance (R) of the resistor. The formula is expressed as V = I × R.

In this case, you have a resistor with a resistance of 2 ohms and a current of 0.5 amperes flowing through it. To calculate the voltage, you would perform the following calculation:

V = 0.5 A × 2 Ω = 1 volt.

Thus, the voltage across the 2-ohm resistor when a current of 0.5 amperes flows through it is indeed 1 volt. This aligns with the basis of electrical principles that describe how current interacts with resistance to produce voltage.