Question

A magnetic dipole has pole strength of 40Am and magnetic length 20cm. what is the magnetic induction at a point on its axis at a distance of 30cm from the centre of the dipole​

Answer 1

Answer:

B) 5.5x10⁻⁵ Wb/m²

Explanation:

B at the axis= μ₀ 2P/4πr³

Where P in the magnetic dipole moment

P=2qa

.°. B= μ₀2(2aq)/4πr³

Given,

2a= 20 cm= 20 x 10⁻²m

q= 40 Am

r= 30 cm= 30 x 10⁻²m

.°. B = 10⁻⁷ x 2 x 40 x 20 x 10⁻²/ (30 x 30 x 30 x 10⁻⁶)

after simplification,

B= 5.9 x 10⁻⁵ ≈ 5.5 x 10⁻⁵ Wb/m²