A dip needle in a plane perpendicular to magnetic meridian will remain

Options

A. Horizontally
B. Vertically
C. in the direction of earth's magnetic field
D. Perpendicular to earth's magnetic field

Answer

To solve the question "A dip needle in a plane perpendicular to magnetic meridian will remain," we will analyze the behavior of a dip needle in relation to the Earth's magnetic field.

### Step-by-Step Solution:

1. **Understanding the Magnetic Meridian**:
- The magnetic meridian is a vertical plane that contains the magnetic field lines of the Earth. It runs from the geographic North to South pole.

2. **Positioning the Dip Needle**:
- A dip needle is a magnetized needle that can pivot freely. When placed in a magnetic field, it aligns itself with the field lines.

3. **Orientation of the Dip Needle**:
- When the dip needle is placed in a plane that is perpendicular to the magnetic meridian, it means that the needle is not aligned with the magnetic North-South direction but is instead oriented in an East-West direction.

4. **Effect of Earth's Magnetic Field**:
- The Earth's magnetic field has both horizontal and vertical components. The vertical component causes the dip needle to tilt.
- In the magnetic meridian, the dip needle would align itself at an angle, but since we are considering a plane perpendicular to this meridian, the vertical component will dominate.

5. **Conclusion**:
- Since the dip needle is in a plane perpendicular to the magnetic meridian, it will align itself vertically due to the influence of the vertical component of the Earth's magnetic field. Therefore, the correct answer is that the dip needle will remain vertically.

### Final Answer:
The dip needle in a plane perpendicular to the magnetic meridian will remain **vertically**.

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