The needle of a dip circle when place at a geomagnetic pole stays along

Options

A. south north direction only
B. east west direction only
C. vertical direction
D. horizontal direction

Answer

To solve the question regarding the behavior of a dip circle needle when placed at a geomagnetic pole, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Dip Circle**:
- A dip circle is an instrument used to measure the angle of dip or inclination of the Earth's magnetic field. It consists of a magnetic needle that can pivot freely.

2. **Concept of Geomagnetic Poles**:
- The geomagnetic poles are the points on the Earth's surface where the magnetic field lines are vertical. There are two such poles: the North Magnetic Pole and the South Magnetic Pole.

3. **Magnetic Field Lines**:
- The Earth's magnetic field lines emerge from the North Magnetic Pole and enter the South Magnetic Pole. At the poles, these lines are oriented vertically.

4. **Behavior of the Needle at the Geomagnetic Pole**:
- When the dip circle is placed at a geomagnetic pole, the magnetic needle aligns itself with the magnetic field lines. Since the magnetic field lines are vertical at the poles, the needle will also point vertically.

5. **Conclusion**:
- Therefore, when the needle of a dip circle is placed at a geomagnetic pole, it will stay aligned vertically.

### Final Answer:
The needle of a dip circle, when placed at a geomagnetic pole, stays along the **vertical direction**.

---