This document discusses magnetic circuits and compares them to electric circuits. It defines key terms like magnetic field intensity H, reluctance, flux φ, magnetomotive force (MMF), and permeability μ. It explains that in a magnetic circuit, flux is determined by MMF, reluctance depends on the material and geometry of the circuit, and reluctance opposes the flow of flux, similar to how resistance opposes current in an electric circuit. Flux is calculated as MMF divided by reluctance.

3. • Introduction
• Magnetic Circuit Laws
• B-H Characteristics
• Classification of Magnetic Materials
• Comparison between Electric and Magnetic Circuits
• Magnetic Hysteresis
• Hysteresis Loss
• Eddy Current and Eddy loss

5. Magnetic Field Intensity H = B/μ

6. Reluctance = (length/area) x (1/Permeability)
= l/Aμ

14. COMPARISION BETWEEN
ELECTRIC AND
MAGNETIC CIRCUIT:

15. • The number of magnetic
lines of force decides the
flux.
• There is flux φ in the
magnetic circuit which is
measured in the weber.
• MMF is the driving force
in the magnetic circuit.
The unit is ampere turns.
• Path traced by the
magnetic flux is called as
magnetic circuit.

16. • The current I = EMF/
Resistance
• R = ρ. l/a.
Directly proportional to
l.
Inversely proportional to
a.
Depends on nature of
material.
• Resistance (R) oppose
the flow of the current.
The unit is Ohm
• The Flux = MMF/
Reluctance
• S = l/ (μ0μra).
Directly proportional to
l. Inversely proportional
to μ = μ0μr.
Inversely proportional to
a
• Reluctance (S) is
opposed by magnetic
path to the flux.
The Unit is ampere
turn/weber.