AC Electrical Quiz 2 Flashcards
What two ways can you look at inductance?
Electrical inertia
Energy stored in an electromagnetic field
What is inductance?
The property of electricity that opposes any change in current due to a change in the electromagnetic field caused by the current
As current increases, what happens to the flux field?
It increases
As current decreases, what happens to the flux field?
It decreases.
If current flow reverses?
The flux field also reverses
Lenz’s Law?
The voltage that is induced into a conductor by a change in the flux field is caused by a change in the current. It is of such a polarity that it opposes the current change which is caused by the change in the flux field
How is inductance measured?
In henries.
What factors affect inductance in an inductor?
Number of wraps in the coil Length of the coil Width of the coil Type of core Total inductance in a circuit
How is total inductance in a series circuit found?
By adding all of the inductors
How is total inductance found in a parallel circuit?
By the inverse sum of the inverses
When will inductance in DC occur?
When the circuit is first closed, when the circuit is first opened, the instant current changes.
What is the only purpose of inductance in DC?
To control the amount of time it takes for total current to flow when the circuit is first closed , or stop when the circuit is first opened.
What is one time constant defined as?
The amount of time it takes in seconds, for 63.2% of the total current to begin to flow in a circuit
How many time constants does it take for total current to flow in a circuit?
Five time constants
Time constant formula?
L/R x5
