Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ELECTRONICS GENERAL > 4001 ELECS - FIRST 450 QUESTIONS > Flashcards

4001 ELECS - FIRST 450 QUESTIONS Flashcards

1
Q

What physical effect will two parallel wires and with the same direction of current flowing over them

A

Attract each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The ratio between the intensity of magnetization produced in a substance, to the source of magnetizing force

A

magnetic susceptibility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

magnetic susceptibility (X) formula?

A

X = M / H
- intensity of magnetization
- source of magnetizing force, magnetic field intensity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

intensity of magnetization formula

A

M = m / V
- m is magnetic moment
- V is volume of material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

magnetic moment formula, 2 formulas

A

m = I x A
m = qvR / 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

source of magnetization is? formula?

A

magnetic field intensity, mmf / l

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The motion of charged particles especially colloidal particles through a stationary liquid under the influence of applied electric fields provided

A

Electrophoresis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What physical motion results from the forces of magnetic fields?

A

motor action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

the term describes a material whose resistance remains relatively constant with changes in the temperature

A

zero temperature coefficient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

which of the following is the resulting effect when electron is made to move?

A

dynamic electricity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

one of the following characteristics of a resistive material which do not change its resistive value with respect to time is its ____.

A

stability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

the time lag of the magnetic flux in a magnetic material, behind the magnetizing force producing it caused by the molecular friction of the molecules trying to allow themselves with the magnetic force applied to the material.

A

Hysteresis

When you apply a magnetic field, the magnetic domains inside the material don’t immediately align with it because of this internal molecular friction. This causes a lag between the applied magnetizing force and the resulting magnetic flux. This lag and retention of magnetization even after the field is removed is what we call hysteresis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What quantity of magnetizing is needed to counterbalance the residual magnetism of a magnetic material?

A

Coercivity is the amount of magnetizing force required to reduce the residual magnetism (or remanence) of a magnetic material to zero

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

measures the resistance of a material to becoming demagnetized

A

coercivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

the amount needed to demagnetize a magnet?

A

coercivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What do you call the magnetic force left in a magnetic material after magnetic induction?

A

residual magnetism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

other term for residual magnetism?

A

remanence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what do you call the flux that does not follow the intended path in a magnetic circuit?

A

leakage flux

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

group of magnetically aligned atoms?

A

domain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

the science of physical phenomena at very low temperature, approaching absolute zero, is called?

A

cryogenics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Theory in magnetism that assumes that all magnetic materials is composed of many tiny magnets?

A

Weber Theory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is used to maintain strength of magnetic field?

A

keeper

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is used to focus the magnetic flux?

A

core

25
Q

when talking about maintaining magnetic field strength we’re talking about ________. when we’re talking about directing magnetic flux resulting to increase in flux density and magnetic field strength, we’re talking about_______.

A

keeper, core

26
Q

the magnetism remaining in a substance or material after the removal of the magnetizing force

A

residual magnetism

27
Q

power rating of carbon-composition resistors?

A

1/8 to 2 watts

28
Q

general power rating of all resistors?

A

1/8 to 5 watts

29
Q

most common resistors? what are their colors?

A

carbon - film and metal - film

brown and blue respectively

30
Q

Material that changes directly from solid to liquid with no plastic or semi-liquid state?

A

Eutectic alloy

31
Q

the definite discrete amount of energy required to move an electron from a lower shell to higher shell?

A

quanta

32
Q

the transfer of energy from one circuit to another circuit by electromagnetic induction is called?

A

transformer action

33
Q

the concept whereby a small voltage is generated by a conductor with current in an external magnetic field refers to _______.

A

hall effect

34
Q

loss of electrical energy in counterbalancing the residual magnetism in each cycle is called _____.

A

hysteresis loss

35
Q

how do you demagnetize properly?

A

apply and AC field and then gradually reduce it to zero

36
Q

what do you call when you properly demagnetize a magnet?

A

degaussing

37
Q

refers to a force of field that exists between ions where they either repel or attract each other

A

potential field

38
Q

what is called the flux density produced within, due to its own induced magnetism?

A

magnetic field intensity

39
Q

what component of dielectric current is proportional to the rate of accumulation of electric charges within the dielectric?

A

absorption current

40
Q

who invented the first electrical instrument used to help gauge the ability of objects to attract, called versorium?

A

william gilbert

41
Q

first electroscope, a device used to detect the presence of static electric charge

A

versorium

42
Q

device used to detect static charges?

A

electroscope

43
Q

typical resistivity range of conductors

A

10^-6 to 10^-4 ohm-cm

44
Q

typical resistivity range of semiconductors?

A

10^-4 to 10^9 ohm-cm

45
Q

typical resistivity range of insulators?

A

10^9 to 10^25 ohm-cm

46
Q

what is the first capacitor?

A

Leyden Jar

47
Q

who invented the Leyden Jar?

A

Pieter van Musschenbroek

48
Q

what is the replacement of Leyden Jar?

A

Electrophorus

49
Q

who invented the electrophorus?

A

Alessandro Volta

49
Q

nonmetallic materials that have ferromagnetic properties?

A

ferrites

50
Q

________ materials have magnetic moments that align in opposite directions, but not equally, so there’s a net magnetization

A

ferrimagnetic

51
Q

ferrites are made of what material?

A

ceramic

52
Q

typical relative permeability of ferrite

A

50 - 200

53
Q

The average permeability is measured where the ______ point is first established.

A

saturation or knee

54
Q

The point on a magnetization curve where an increase in the applied magnetic field 𝐻 results in little to no increase in magnetization 𝑀. It’s where the material is “saturated” with magnetic flux.

A

saturation or knee point

55
Q

for certain magnetic material, the ______ the area inside the hysteresis loop, the ______ the hysteresis loss

A

larger, higher

56
Q

In a magnetic circuit, what loses are caused by reversing current direction thousands of times in a coil?

A

hysteresis loss

57
Q

why is a two-pole magnetic field set up around a coil

A

because separate lines of magnetic force link and combine their effects

ELECTRONICS GENERAL (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions