A N-pole of a very long magnetic needle is placed at a distance of 20 cm from a point 'P'. If the pole strength of the magnetic needle is 40 Am what is the magnetic induction at the point 'P'?

Explanation

To solve the problem, we need to calculate the magnetic induction (B) at point P due to a north pole of a magnetic needle. We will use the formula for the magnetic induction due to a magnetic pole:

\[ B = \frac{\mu_0 \cdot m}{4 \pi d^2} \]

Where:
- \( B \) is the magnetic induction,
- \( \mu_0 \) is the permeability of free space (\( 4 \pi \times 10^{-7} \, \text{T m/A} \)),
- \( m \) is the pole strength (in Am),
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