Brainscape's Knowledge GenomeTM

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


See full index

Physics 30 > Fields > Flashcards

Fields Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

Law of electric charges.

A

Like charges repel. Unlike charges attract.

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

Law of conservation of charge.

A

Charge can be transferred from one object to another, but the total charge of a closed system remains constant.

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

Elementary charge.

A

1.602*10^-19 C

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

Coulomb’s Law.

A

The force between two point charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between the charges.

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

Where does an electric field exist?

A

Where a test charge placed would have a force exerted on it.

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

What are electric fields?

A

electric force / charge

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

What is field strength not dependent on when between two charged plates?

A

Distance from either plate. It is uniform between the two.

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

What is the unit for electric potential energy?

A

Voltage. (Joule per Coulomb)

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

What are the symbols for gravitational, electric and magnetic fields?

A

Gravitational: g
Electric: ε
Magnetic: B

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

How does the strength of fields and distance relate?

A

Inverse square law.

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

How did Newton explain gravity?

A

Mass attracts mass.

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

Paths of planets are…

A

Ellipses with the centre of the sun at one focus.

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

A line segment joining a planet and the sun…

A

Sweeps out equal areas during equal intervals of time.

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

Kepler’s Law.

A

k=R^3 / T^2
This constant applies to all orbits.

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

How much is 1 A.U?

A

1 astronomical unit is the average distance between the Earth and the Sun.

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

How did Einstein explain gravity?

A

Mass warps spacetime. This means that gravity is not a force. Objects trace geodesics (paths of least action through spacetime) unless acted on by a net external force.

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

What is the principle of equivalence?

A

Absence of a gravitational field (true weightlessness) is indistinguishable from free fall acceleration (apparent weightlessness).

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

Do neutral objects (not particles) attract to charged objects?

A

Yes. A positive charge will attract negative charges within an object create an imbalance and attraction. A negative charge will repel negative charges within an object creating an imbalance and attraction.

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

What are the ways to build electrostatic charge?

A

Friction. Conduction. Induction.

20
Q

What determines the quantity of charge on an object?

A

The number of elementary particles on the object multiplied by the elementary charge (e)

q=Ne

21
Q

What is an electric field?

A

A region surrounding a charge that exerts a force on charges within the field.

22
Q

What is direction in an electric field?

A

The direction that a positive charge will move.

23
Q

What is electric potential difference?

A

Voltage.

24
Q

Do electric and/or magnetic fields need both poles?

A

Electric fields can have 1 pole.
Magnetic fields always have two.

25
Q

What are the units for magnetic fields?

A

Teslas (T)
N/(Cm/s)

26
Q

What rule do you use to determine the direction of force on a charge moving through a magnetic field?

A

Right hand rule for positive charges.
Left hand rule for negative charges.

27
Q

How do you determine the magnetic field direction around a wire?

A

Right hand rule #2.

Point thumb in direction of conventional current. Curl fingers. Direction fingers move in is direction of magnetic field.

28
Q

What is mass spectrometry?

A

An analytical technique that identifies the chemical composition of a compound or a sample based on the mass to charge ratio of the charged particle.

29
Q

What is current?

A

The flow of charges. Amperes (I).
I=C/s

30
Q

What is a solenoid?

A

A coil of wires. When current flows through it, it becomes an electromagnet.

31
Q

How does velocity proportionally relate to radius of orbit around the Sun?

A

Velocity drops off at an inversely proportional rate.

32
Q

How does velocity of orbit change with radius of orbit around a galaxy?

A

It does not appear to change.

33
Q

How can the Sun’s mass be estimated?

A

Using a planets orbit and speed.

34
Q

Why does measuring the mass of galaxies using the brightness method get less than using the orbital method?

A

There must be a large amount of unseen mass.

35
Q

Observations that indicate dark matter have been found in…

A

Every galaxy that has been examined.

36
Q

Evidence for dark matter comes from…

A

Orbits of the stars and gravitational lensing.

37
Q

Mass found by gravitational lensing method agrees with…

A

Orbital method

38
Q

Why is dark matter called “dark”?

A

It does not emit or reflect any radiation.

39
Q

What do most physicists think dark matter is made of?

A

WIMPs or Axions.

40
Q

How much is known about dark matter?

A

There are some ideas about it which are currently being tested.

41
Q

What is motor force?

A

The force that a magnet exerts on a current-carrying conductor. F=ILB*sin(ϴ)

42
Q

What happens with parallel conductors?

A

They either attract or repel each other depending on their directions of current. Same direction, attraction. Opposite direction, repulsion.

43
Q

What is Ampere’s law?

A

The cable’s internal magnetic field, B, is directly proportional to the current, I, and inversely proportional to the circumference.
B=μI / 2πr

44
Q

What happens when a charged object touches a neutral object?

A

Electrons transfer between them to balance out. Ex: A positive object will take some electrons, making the neutral object positive as well. A negative object will give some electrons, making the neutral object negative as well.

45
Q

What is electric potential energy?

A

The energy stored in the system of two charges a certain distance apart.

Physics 30 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions