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Flashcards in Unit 1 Deck (42)
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1
Q

What is electricity

A

movement of e-

2
Q

What is ampere

A

strength of the current (charge over time)

3
Q

What is electric field

A

force exerted by an electric charge

4
Q

What is electrical potential energy

A

the energy needed to affect other electric charges

5
Q

What is impedance

A

opposition to the magnitude and phase of a current

6
Q

What is resistance

A

opposition to the magnitude of a current (similar to friction)

7
Q

What is capacitance

A

ratio of the change in an electric charge

8
Q

What is DC

A

electric current that is unchanging; resistance and impedance are the same

9
Q

What is AC

A

electric current that periodically reverses direction; resistance and impedance are not the same

10
Q

What is magnetic field

A

vector field created by electric charges in relative motion

11
Q

What is electrodynamics

A

the interaction s between electric charges and currents

12
Q

What is electromagnet

A

magnetic field created by an electrical curren

13
Q

What is magnetic domain

A

region of a magnetic field that is in a uniform direction

14
Q

What is magnetic susceptibility

A

extent to which a material is affected by a magnet

15
Q

What is Tesla

A

unit of measure for magnetic force (1T=10,000G)

16
Q

What is Gauss

A

unit of measure for magnetic force (earth’s magnetic force = 0.5G)

17
Q

What is the phase

A

waveform of going through a complete cycle

18
Q

What is electromagnetic induction

A

production of a current due to the motion of a magnetic field

19
Q

What is electromagnetic radiation

A

EM waves interactions w/ matter

20
Q

How do like and unlike electric charges interact

A

likes repel; opposites attract

21
Q

how does distance affect the strength of electrostatic charges

A

inverse square law

22
Q

Ohm’s Law

A

I=V/R

I - current; V - voltage; R - resistance

23
Q

Describe an insulator

A

resists the effects of a current

24
Q

Describe a conductor

A

easily carries a current

25
Q

Describe a semiconductor

A

conductivity between an insulator and a conductor

26
Q

Describe a superconductor

A

conductor that never loses a current

27
Q

Ferromagnetic

A

highly susceptible to magnetic force

28
Q

paramagnetic

A

partially susceptible to magnetic force

29
Q

Diamagnetic

A

not affected by magnetic force

30
Q

Temporary magnet

A

magnetization is applied or removed when exposed to a magnetic force

31
Q

Permanent magnet

A

magnetization isn’t affected by a magnetic force

32
Q

How do like and unlike magnetic poles interact

A

opposites attract; likes repel

33
Q

how does distance affect magnetic field strength

A

inverse square law

34
Q

Faraday’s Law (of electromagnetic induction)

A

V = -dB/dt

V - Electromotive force; dB - change in the magnetic field; dt - change in time

35
Q

types of impedance

A

Resistors - release of energy through heat
Capacitor (plates) - energy is stored in an electric field
Inductor (coils) - energy is stored in a magnetic field

36
Q

physical causes of electromagnetic radiation

A

radio waves, light, heat

37
Q

What are the orientations of the magnetic domains in a magnet?

A

they oscillate, 90 degrees out of phase, perpendicular to each other

38
Q

How is the magnetic field affected if a current is looped?

A

amplifies the magnetic field

39
Q

What is the orientation of an induced magnetic field to the current

A

counter clockwise (right hand rule)

40
Q

What do the waveforms look like when they are in phase?

A

overlapping sine waves

41
Q

What do the waveforms look like when they are 90 degrees out of phase?

A

sine and cosine waves

42
Q

What do the waveforms look like when they are 180 degrees out of phase?

A

sine and -sine waves