Inductance + RL Circuits

Question 1

Describe an Inductor

Answer 1

wound Coil of wire with a ferrite metal or Air was its core

Question 2

What is the Unit for Inductance

Answer 2

Henrys (H)
size of inductance is given the letter L

Question 3

If a sinusoidal voltage supply is connected to an inductor, describe the relationship between the voltage function and the current function

Answer 3

Voltage leads current by 90 degrees or Pi Radians

Question 4

How do you calculate the B Field material property using amperes law

Answer 4

Question 5

what is Faradays Law

Answer 5

The amount of Induced voltage in a conductor is directly proportional to the rate of change in the magnetic field flux

Question 6

what is Lenz’s Law

Answer 6

The voltage induced is such that it opposes the change in magnetic flux

By generating a current which opposes the change in magnetic flux

Question 7

Explain the concept of self inductance

Answer 7

This means that if the current increases the direction of induced voltage in the coil will oppose the increase in current. And Vice Versa

Question 8

Derive the Formula for calculating the size of the induance

Answer 8

Question 9

what formula uses amperes law to calculate the magnetic field within a coil?

Answer 9

Question 10

How do you calculate Reactive Inducance

Answer 10

jωL

Question 11

if two inductors are placed in series how do you calculate total inductance?

Answer 11

same as series resistors

Question 12

if two inductors are placed in parallel how do you calculate total inductance?

Answer 12

same as parallel resistors

Question 13

What is the Step Response of an inductor

Answer 13

Question 14

how do you calculate total impedance of an RL circuit

Answer 14

Question 15

How do you calculate the phase shift between voltage and current in an RL circiuit

Answer 15

Question 16

Whats important to note about a Parallel RL circuit

Answer 16

Supply Voltage , Inductance Voltage and Reistor voltage must all be in phase and of same magnitude.

Current Down inductor must lag its voltage by Pi radians

So Current down resistor leads current down inductor by Pi radians

Question 17

How do you calculate total impedance of a parallell RL circuit?

Answer 17

Question 18

explain why the function for instantaneous power is twice the frequency of voltage or current

Answer 18

Question 19

Explain how inductors store and release energy

Answer 19

Inductors store energy in the magnetic field

Energy is released when the change in current / Change in time changes direction

Question 20

Answer 20

Question 21

how do you calculate the size of the magnetic field around a wire

Answer 21