The direction of magnetic field around a current carrying conductor is given by

Options

A. Fleming's left hand rule
B. Right hand thumb rule
C. Both (a) and (b)
D. None of these

Answer

To determine the direction of the magnetic field around a current-carrying conductor, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Current Direction**:
- First, we need to know the direction of the current flowing through the conductor. For this example, let's assume the current is flowing upwards.

2. **Use the Right-Hand Thumb Rule**:
- The right-hand thumb rule is a simple way to find the direction of the magnetic field. According to this rule, you should hold your right hand in such a way that your thumb points in the direction of the current.

3. **Curl Your Fingers**:
- With your thumb pointing in the direction of the current, curl your fingers around the conductor. The way your fingers curl indicates the direction of the magnetic field lines around the conductor.

4. **Determine the Magnetic Field Direction**:
- If your thumb is pointing upwards (in the direction of the current), your fingers will curl in a specific direction (either clockwise or anti-clockwise) around the conductor. In this case, if you look from above, your fingers will curl anti-clockwise.

5. **Conclusion**:
- Therefore, the direction of the magnetic field around the current-carrying conductor is anti-clockwise when viewed from above.

### Final Answer:
The direction of the magnetic field around a current-carrying conductor is given by the **Right-Hand Thumb Rule**.