Calculate the potential difference across a 10 resistor carrying current of 2 A.

Resistance $R = 10 \Omega$
Current $I = 2 \text{ A}$

The formula for Ohm's Law is $V = IR$.

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The potential difference across a 3 $\Omega$ resistor is 12 V. What is the current flowing?

Resistance $R = 3 \Omega$
Potential difference $V = 12 \text{ V}$

Rearranging Ohm's Law $V = IR$ for $I$:

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Find the potential difference across a conductor of resistance 2 $\Omega$ if the charge of 180 C flows for 2 minutes.

Resistance $R = 2 \Omega$
Charge $Q = 180 \text{ C}$
Time $t = 2 \text{ minutes} = 2 \times 60 \text{ s} = 120 \text{ s}$

The formula for Ohm's Law is $V = IR$.

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A current of 4 A flows through an electric kettle. The p.d. across it is 8 V. Find the resistance.

Current $I = 4 \text{ A}$
Potential difference $V = 8 \text{ V}$

Rearranging Ohm's Law $V = IR$ for $R$:

:
The potential difference across a 2 k$\Omega$ resistor is 4 V. Determine the current flowing in the circuit.

Resistance $R = 2 \text{ k}\Omega = 2 \times 10^3 \Omega = 2000 \Omega$
Potential difference $V = 4 \text{ V}$

Rearranging Ohm's Law $V = IR$ for $I$:

This can also be expressed in milliamperes: