A magnetic needle suspended in a vertical plane at `30^@` from the magnetic meridian makes an angle of `45^@` with the horizontal. Find the true angle of dip.

Explanation

To solve the problem of finding the true angle of dip when a magnetic needle is suspended at an angle of \(30^\circ\) from the magnetic meridian and makes an angle of \(45^\circ\) with the horizontal, we can follow these steps:

### Step 1: Understand the given information
- The angle from the magnetic meridian, \( \theta = 30^\circ \).
- The apparent angle of dip, \( \delta_1 = 45^\circ \).

### Step 2: Use the relationship between true dip and apparent dip
The relationship between the true angle of dip \( \delta \) and the apparent angle of dip \( \delta_1 \) is given by the formula:
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