What is the magnetic induction due to a magnet of pole strength 20A-m and length 20 cm at a distance of 0.5m from its centre on the axial line?

Explanation

To find the magnetic induction \( B \) due to a magnet of pole strength \( m = 20 \, \text{A-m} \) and length \( l = 20 \, \text{cm} \) at a distance \( r = 0.5 \, \text{m} \) from its center on the axial line, we can follow these steps:

### Step 1: Convert Length to Meters
The length of the magnet is given as \( 20 \, \text{cm} \). We need to convert this to meters:
\[ l = 20 \, \text{cm} = \frac{20}{100} \, \text{m} = 0.2 \, \text{m} \]

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