Inductors Flashcards
1
Q
What is the flux linkage?
A
NΦ_B with units of Weber
2
Q
What is the self-inductance?
A
L=NΦ_B/I
3
Q
What is the self-induced emf in an inductor?
A
ϵ=-LdI/dt
4
Q
What is the inductance of a solenoid?
A
L=NΦ_B/I=μ_0N^2A/l
5
Q
What is the magnetic field energy?
A
U=LI^2/2
6
Q
What is the magnetic energy density?
A
u=U/V=B^2/2μ0
7
Q
How do inductors add in series?
A
L_eq=L1+L2
8
Q
How do inductors add in parallel?
A
1/L_eq=1/L1+1/L2
9
Q
What is a transformer?
A
Two inductors coupled by a ferromagnetic core
10
Q
What is the equation for a transformer?
A
ϵ_s/N_s=ϵ_p/N_p
11
Q
How do we determine the type of transformer?
A
For N_s>N_p: step up
For N_s<N_p: step down
12
Q
What is the current in a trasnfomer?
A
ϵ_s I_s=ϵ_p I_p
N_s I_s=N_p I_p
