Brainscape's Knowledge GenomeTM

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


See full index

Introductory Physics 2 > Chapter 20 > Flashcards

Chapter 20 Flashcards

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

Like charges do what?

A

Like charges repel each other

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

opposite charges do what?

A

opposite charges attract each other

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

what does neutral mean?

A

an object has no charge or the net charge is zero

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

what does charging mean (acquired charge)?

A

most things are electrically neutral, they have equal amounts of negative and positive charges. We can use certain materials to help them acquire charge. Most materials are divided into 3 categories

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

what are the 3 categories of materials used to charge objects?

A
  1. Charging by Friction
  2. Charging by Contact
    3: Charging by Induction:
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is charging by friction?

A

this is useful for charging insulators, if you rub one material with another, electrons have a tendency to be transferred from one material to the other

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

what is charging by contact?

A

This is useful for charging metals and the conductors, If a charged object touches a conductor, some charge will be transferred between the object and the conductor, charging the conductor with the SAME sign as the charge on the object

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

what is charging by induction?

A

Also useful for charging metals and other conductors, a charge object is brought near/close to the conductor and does NOT touch iT, if the conductor is on the ground electrons will either flow away from it or onto it. when the ground connection is removed the conductor will have a charge OPPOSITE in sign to that of the object

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

what is electrical force?

A

the LONG-RANGE FORCE between charged objects, it can be repulsive or attractive
- gravity is another long-range force, but it is always attractive

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

what are the two types of electric charges that exist?

A
  1. positive (proton)

2. negative (electron)

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

electric charge is always what?

A

electric charge is always conserved!

- objects become charged because negative charge is transferred from one object to another

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

what is nature’s basic carrier of a positive charge?

A

The proton!

- protons do not move from one material to another because they are held firmly in the nucleus

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

what is nature’s basic carrier of the negative charge?

A

The electron!

- gaining or losing electrons is how an object becomes charged

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

electric charge is?

A

electric charge is QUANTIZED: it comes in units of the fundamental charge
unit : Coulomb (C)
e = 1.6x10^-19 C

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

what is a conductor?

A

conductors are materials in which the electric charges move freely in response to an electric force.

  • ie) metals; copper, aluminum and silver
  • ADDED charge redistributes itself quickly over conductors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is an insulator?

A

insulators are materials in which electric charges do not move freely.

  • ie) plastics; glass, rubber
  • when insulators are charged by rubbing, ONLY the rubbed area become charged, hey don’t distribute themselves evenly
17
Q

what is electrostatic equilibrium?

A
  • charges on an insulator do not move

- charges on a conductor adjust until there is no net force on any charge

18
Q

What is the Charge model?

A

The basic postulates of charges and charging

19
Q

what does ground/grounded mean?

A

basically anything neutral that give up electrons to, or take electrons from, an object

20
Q

what is Coulomb’s Law?

A

The electric force between two point charges:
- is directed along the line joining the two particles
- is inversely proportional to the square of the separation distance (r) between them
- is proportional to the product of the magnitude of the charges |q1| & |q2| on the two particles
- is attractive if the charges are of opposite sign and repulsive if the charges have the same sign
K = 8.99x10^9 Nm^2/C^2
F2on1 = F1on2 = k|q1||q2|/r^2

21
Q

Electrical force vs Gravitational force?

A

Electrical force is much stronger than gravitational force, which only has a G=10^-10 & K=10^+10
Fgravity = Gm1m2/r^2 = Felectric = K|q1||q2|/r^2

22
Q

Vector Addition of Electric Forces?

A

The net force exerted on particle j is?
Fnetonj = F1onj + F2onj + F3onj…..
- Add vectors up by breaking them up into their components

23
Q

what Is an Electric Field?

A
  • The electric field at a point in space tells you how much force +1C charge would feel if it were placed at that point
  • The electric field gives the force per unit charge
  • The electric field is a vector quantity
  • SI units of electric field are Newtons/Coulomb (N/C)

E = F/q = K|q|/r^2

24
Q

what is the direction of an electric field?

A

The direction of the field is radially outward from a positive charge, or radially inwards towards a negative charge

25
Q

What is the direction of an electric field between charged plates?

A
  • The electric field points from the positive to the negative plate
  • the field is uniform
    E = Q/E0*A
26
Q

what is an electric field like mea a continuous charge distribution?

A
  • divide the total charge (Q) into (n) mini-segments with charge (ΔQ)
  • treat each mini-segment as a point charge, and find the field due to each mini-segment
  • add the fields due to each mini-segment, component by component
  • The same becomes an integral as n->∞
27
Q

what are electric field lines?

A

A convenient aid for visualizing electric field patters is to draw lines pointing in the direction of the field vector at any point
- the electric field is tangent to the electric field lines at each point

28
Q

what are the electric field line patterns?

A
  1. for a positive source charge, the lines radiate outward

2. for a negative source charge, the lines point inward

29
Q

The high density of lines means what?

A

The high density of lines between the two charges indicates the strong electric field in this region

30
Q

What is an electrocardiogram?

A

an electrocardiogram measures the changing field of the heart as it beats

31
Q

Motion of charged particles in an electric field?

A
  • If a particle has a mass (m) and a charge (q) is placed in an electric field, it will feel a force
    F = qE therefore a = F/m = qE/m
  • If E is uniform then the particles acceleration is constant. in this case our KINEMATICS FORMULA apply

Introductory Physics 2 (10 decks)

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