the phenomenon of electric current generation in a closed conducting loop when the magnetic flux passing through it changes
Lorentz force formula: F = q·E + q·v×B — force acting on a charged particle in electric and magnetic fields
The force acts on a charge q moving with velocity v in a magnetic field B, at an angle α to the field direction. Maximum at α = 90°, absent at α = 0°.
Ampere force formula: FA = I·l·B·sin(α) — force acting on a current-carrying conductor in a magnetic field, depends on current, conductor length, magnetic induction, and the angle between them
Force acting on a conductor of length l with current I, located in field B at angle α. Direction is determined by the left-hand rule.
Magnetic moment of a loop formula: M = I·S·B·sin(α) — moment acting on a current loop in a magnetic field, depends on current, loop area, magnetic induction, and the angle between the normal and the field
Moment acting on a loop of area S with current I in a magnetic field B. Ensures loop rotation and is fundamental to electric motor operation.
Magnetic flux formula: Φ = B·S·cos(α) — product of magnetic induction, surface area, and cosine of the angle between the field direction and the normal to the surface
Magnetic flux Φ is the number of magnetic induction lines passing through surface S at angle α. The greater the field and area, the higher the flux. Maximum at α = 0°.
Magnetic field strength formula: H = I / (2·π·r) — depends on current strength and distance to the conductor
Strength H depends on current I and distance r from the conductor. The closer to the conductor, the stronger the field. Direction by the right-hand rule (Corkscrew rule).
Induced EMF formula: εF = –N·ΔΦ/Δt — electromotive force is proportional to the rate of change of magnetic flux through the loop
EMF arises from a change in magnetic flux through a loop. N — number of turns, ΔΦ — change in flux, Δt — time interval. The minus sign reflects opposition (Lenz's law).
Self-induced EMF formula: ε = –L·ΔI/Δt — electromotive force arising from a change in current in a circuit, proportional to inductance and the rate of change of current
EMF arises from a change in current in a circuit with inductance L. ΔI — change in current strength, Δt — time interval. Self-induction is the phenomenon of EMF generation within the circuit itself.
Formula for magnetic field energy of a coil: WM = (L·I²)/2 — energy stored in a coil with inductance when current flows
Energy accumulates in a coil with inductance L when current I flows. Proportional to the square of the current — similar to kinetic energy in mechanics.
Formula for magnetic field energy: WM = Φ·I / 2 — energy stored in a coil, expressed through magnetic flux and current strength
The formula is applied when magnetic flux Φ and current I are known. Provides equivalent field energy through circuit parameters.
Formula for magnetic field energy: WM = Φ² / (2·L) — energy stored in a coil, expressed through the square of magnetic flux and inductance
Useful for calculations when field flux and inductance are known. Applied in oscillation theory and resonant circuits.