Question

The resistance of a conductor is said to be $1\Omega$ if:

• A. 1 ampere of current flows through it when the potential difference across the ends is 0
• B. 0 ampere current flows through it when the potential difference across the ends is 1 volt
• C. 1 ampere of current flows through it when the potential difference across the ends is 10 volt
• D. 1 ampere of current flows through it when the potential difference across the ends is 1 volt

Answer 1

The correct option is D

1 ampere of current flows through it when the potential difference across the ends is 1 volt

According to Ohm’s law $V=I\times R$ where V = voltage, I = current and R = resistance.
Therefore, $R=\frac{V}{I}=\frac{1V}{1A}=1\Omega$
Thus $1\Omega$ is the resistance any material offers to flow of 1 ampere of current when the difference of potential applied between the two ends of the material is 1 volt.