*Question T5D12:
What is the voltage across a 10-ohm resistor if a current of 2 amperes flows through it?*  

*Correct Answer is  D: 20 volts*  

### AI Response: (may contain errors)  

To find the voltage across a resistor when a current flows through it, we can use Ohm's Law, which states:

$$V = I \times R$$

where:
- $V$ = voltage in volts
- $I$ = current in amperes
- $R$ = resistance in ohms

In this case:
- $I = 2$ amperes
- $R = 10$ ohms

Now, substituting the values into the formula:

$$V = 2 \, \text{A} \times 10 \, \Omega = 20 \, \text{V}$$

This shows that the voltage across the 10-ohm resistor is 20 volts, which is why the correct answer is **D: 20 volts**.

### Explanation of Other Choices:
- **A: 8 volts**  
  This is incorrect because it does not follow Ohm's Law. If we calculate using $V = I \times R$, we do not arrive at this value.

- **B: 0.2 volts**  
  This is also incorrect. It seems to be a miscalculation, possibly from using an incorrect formula or misunderstanding the relationship between current and voltage.

- **C: 12 volts**  
  This choice is incorrect as well. It does not match the calculation from Ohm's Law for the given current and resistance.

### Summary:
- Use Ohm's Law to calculate voltage across a resistor.
- The formula is $V = I \times R$.
- For a 10-ohm resistor with 2 amperes of current, the voltage is 20 volts.