What is the voltage drop across resistor R1 when R1 is 6 ohms and the voltage is 12 volts?

The voltage drop across a resistor in a simple circuit can be calculated using Ohm's Law, which states that the voltage (V) across a resistor is equal to the current (I) flowing through it multiplied by the resistance (R).

In this case, the total voltage provided in the circuit is 12 volts. When we examine a situation where a single resistor (R1) with a resistance of 6 ohms is connected directly across this voltage source, the entire voltage of the power source will appear across the resistor because it is the only component in the circuit. This is due to the concept of series and parallel connections.

If R1 is the only resistor or the first resistor in a series circuit, the voltage drop across it will be equal to the total voltage supplied (12 volts). Hence, the voltage drop across R1 is indeed 12 volts, aligning with the response indicating that option is the correct answer.

This demonstrates that when a resistor is directly connected to a voltage source without any other resistors affecting the circuit, it will experience the full voltage supplied by the source. Thus, the answer of 12 volts is confirmed to be accurate.