symbols, units and equations

• Magnetic field strength, symbol B, unit tesla (T)
• Magnetic flux, symbol Φ, unit webber (Wb)
• Strength (B) is defined as the magnetic flux density. The increase in the n.o. mag. field lines per unit area means a stronger field.
• magnetic flux -> Φ = B x A

  magnetic field strength -> B = Φ/A
• Area, symbol A, unit meters squared (m²)
• Magnetic force on moving charge -> FB = q x V x B
• Charge, symbol q, unit coulomb (C)
• speed, symbol V, unit meters per second (Ms-1)
• Mag. flux is defined as the total number of mag. field lines passing through any surface or conductor

  
  

  Flux = mag. field lines
• Max flux when fields lines are perpendicular

  Zero when parallel
• Current, symbol I, unit amps (A)
• length of wire in the field, symbol L, unit meter (M)
• force on a current carrying wire -> FB = B x I x L
• induced voltage across a straight metal wire moving in a mag. field -> Vinduced = B x V x L
• I induced = Vinduced/R
• (E) Vinduced = - △Φ/ △t
• area of a circle = πr$^2$
• total flux = Φ x n.o. turns
• when Φ = 0, E is max

  when Φ max, E = 0
• average voltage induced in coil while its being rotated -> V = -n △Φ/t
• △= change in ...
• time for current to drop to zero -> V = -n △Φ/t => t= -n x △Φ/ V
• average rate flux changes during time interval -> △Φ/△t
• total resistance = R per turn x N.O. turns
• average current in loop -> I = V/Tr (T=total)
• Φ = LI
• Inductance of coil, symbol L, unit henry (H)
• Vinduced = - △Φ /△t => Vinduced = -L △I/△t
• time taken for current to drop to zero -> t = -L x I△/V
• self inductance of coil -> -L = V/ (△I/△t)
• time interval -> T = L/R
• time constant, symbol T, unit seconds (s)
• energy stored in an inductor -> E=1/2LI²
• resistance -> r = V/I
• resistance, symbol R, unit ohms (Ω)
• Vs induced = -M △Φp/△t -> = -M △Ip/△t
• mutual inductance, symbol M
• P = I x V
• Pheat = I² x R
• Vs = supply voltage