Units and Equations - Section 2 Flashcards
Magnetic Fiel Equation
B = F/|q0|(v X sin (theta))
Magnetic Field Units
Newton X Second/Coulomb X meter = Tesla
Centripetal Force
F(c) = mv^2/r
r= mv/|q|B
Magnectic Force on a current carrying wire of a certain length
F = ILB X sin (theta)
Net torque on a current carrying coil
t = NIA X (B X sin (theta))
N= # of turns in coil A= length X width
Magnetic moment
NIA
Magnectic moment units
Ampere X meter^2 (A X m^2)
Torque units
Newton X meter
Magnetic Field of a wire
B = (u0 X I)/(2)(pi)(r)
Magnetic Field of a circular loop
B = N X (u0 X I0/2R
Magnetic Field of a solenoid
B = u0 X n X I
Permeability of free space
u0 = 4pi X 10^-7 T X m/A
Ampere’s Law
Sum of (B||delta L) = u0 X I
Motional EMF equation
& = vBL
v=velocity
L=length
Motional EMF units
Volts
Magnetic Flux equation
BA X cos (theta)
Magnetic Flux units
Tesla X meter squared = Weber (Wb)
Farraday’s Law of Electromagnetic Induction
& = - N X (change in magnetic flux/ change in time)
N = # of loops in coil
Induced emf in a rotating planar coil in a generator
& = NABw X sin (theta)
theta = wt w= 2(pi)f
NABw = &max
Current drawn by a motor
I = V - &/ R
R= resistance
Emf due to mutual inductance
&(s) = -M X (change in current in primary coil / change in time)
M = # of loops in secondary X magnetic flux of secondary / current in primary
Mutual inductance units
V X s/A = Henry (H)
Emf due to self inductance
& = -L X (change in current / change in time)
L = # of loops X magnetic flux / change in time
Self inductance units
V X s/A = Henry (H)
Energy stored in an inductor
E = .5 X LI^2
L = self inductance
Energy Density
Energy/Volume = 1/2(u0) X B^2
Transformer equation
V(s) / V(p) = N(s) / N(p)
I(s) / I(p) = N(p) / N(s)
