A bar magnet of magnetic moment `0.4Am^(2)` is placed in the magnetic meridian with its north pole pointing north. A neutral point is obtained at a distance of 10 cm from the centre of the magnet. If the length of the magnet is also 10 cm, what is the value of horizontal component of earth's field at the place?

Explanation

To solve the problem, we need to find the horizontal component of the Earth's magnetic field at a point where a neutral point is observed due to a bar magnet. Here’s a step-by-step solution:

### Step 1: Understand the Given Data
- Magnetic moment of the bar magnet, \( m = 0.4 \, \text{Am}^2 \)
- Length of the bar magnet, \( L = 10 \, \text{cm} = 0.1 \, \text{m} \)
- Distance from the center of the magnet to the neutral point, \( d = 10 \, \text{cm} = 0.1 \, \text{m} \)

### Step 2: Calculate the Length from Center to End
...