A bar magnet has five lines of force cutting one square centimeter (1 cm2). Assuming that each line of force represents 30 Wb of flux, the flux density for the magnet is

The magnetic flux density is 3 x 10⁵ Wb/m²

Explanation:

Given;

magnetic flux of each line of force, Ф = 30 Wb

area of the bar magnet, A = 1 cm² = 1 x 10⁻⁴ m²

The flux density of the magnet is the measure of the concentration of the magnetic flux per unit area. The unit is Wb/m² or Tesla.

B = Ф / A

B = 30 / (1 x 10⁻⁴ )

B = 3 x 10⁵ Wb/m²

Therefore, the magnetic flux density is 3 x 10⁵ Wb/m²

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