Question

mild steel ring has a mean diameter of 160 mm and a cross sectional area of 300 mm2. The relative permeability of mild steel is 1120.​

Answer 1

Answer:

Step-by-step explanation:

 MMF = φR

where,

magnetic flux: φ = 400 webers

reluctance: R = µ ℓ / A

permeability of free space: µo = 4πx10^-7 Wb/A-m

effective permeability: µ = kµo = (1120 *4πx10^-7)

length: ℓ = (2π*(160/2)x10^-6 m

cross-sectional area of ring: 300x10^-6 mm²

MMF = 400*(1120*4πx10^-7)(2π*(160/2)x10^-6 / 300x10^-6

MMF = 0.51 A t