Brainscape's Knowledge GenomeTM

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


See full index

G9 + 10 physics > unit 4 - electricity > Flashcards

unit 4 - electricity Flashcards

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

Static Electricity

A

Study of charges at rest

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

Current Electricity

A

Study of charges in motion

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

When do we get a shock?

A

When accumulated charges present within our body leave our body

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

Electrical field

A

Region or space around a charged body in which its effect can be felt by other charged bodies

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

Coulombs law of electrostatics, also known as

A

Inverse Square law

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

Coulombs law of electrostatics defination

A

The electrostatic force of attraction or repulsion between 2 point charges is directly proportional to the product of their charges and inversely proportional to the square of the distance between them

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

Coulombs law final equation with constant

A

F = k (q_1 * q_2)/r^2

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

What is coulombs constant?

A

Represented with K
Constant:
Value in free space/air/vacuum = 9 * 10^9
Dependent on medium and changes with each medium

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

Properties of charges

A
  1. There are 2 types of charges (+ve and -ve)
  2. Like charges repel, opposites attract
  3. Quantization of charge
  4. Law of conservation of charge
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is law of conservation of charge

A

Charge can neither be created nor destroyed, it can only be transferred from one body to another

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

What is quantization of charge

A

The net charge acting on a body is always an integral multiple of the elementary charge

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

What is quantization of charge formula?

A

Q = ± n * e
Q = net charge
n = integer/no. of electrons being transferred
e = elemntary charge

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

What is the elementary charge

A

Constant
represented with e
Least amount of charge that could be present on a stable body
Value = 1.60 * 10^-19 C

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

Transfer of charge through friction

A

Obstructs relative motion, generating heat between two bodies being rubbed, allowing the free electrons to gain enough energy to get ejected to a different body. With enough energy, the electrons can jump from one body to another allowing for flow of charge

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

transfer of charge through induction

A

The process of charging a neutral body by bringing it near another charged object, but there is no physical contact between the two

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

What happens to charges within a neutral body in induction

A

The charges get redistributed due to the influence of a charged object

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

Transfer of charge through conduction

A

The process of charging a body which involves direct physical contact between the neutral and charged objects, allowing for charge to flow between the objects

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

Electrons within insulators

A

Tightly held together with the atom and are not free to move around although they can be transferred by rubbing

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

Earthing

A

The process of electrons flowing from a charged body onto the earths ground

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

Potential at a point

A

Amount of work done per unit positive test charge in moving a small charge from infinity to that point

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

Formula of potential at a point and si unit

A

V = W/q

Si unit = volt

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

Charge will flow from where to where

A

From a point at higher potential to a point at lower potential by itslef

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

2 general statements about point charges closer to positive and negative sources

A

Points closer to a +ve source charge will be at a higher potential
Point closer to a -ve source charge will be at a lower potential

24
Q

Current

A

Rate of flow of charge

25
Q

Current flow is dependant on?

A

Potential difference, higher potential difference means a higher current

26
Q

Formula for current and si unit

A

I = q/t

Si unit - Ampere

27
Q

Ohms law

A

For all external conditions such as temperature remaining constant, the current flowing is directly proportional to the potential difference applied across the 2 ends

28
Q

Formula for Ohms law =

A

V = IR

29
Q

Conventional current flow

A

Flows from positive terminal (high potential) to a negative terminal (low potential). Always opposite the flow of electrons

30
Q

Ohmic conductor w/ examples

A

Those conductors which obey ohms law like iron copper and gold

31
Q

non ohmic conductors with examples

A

Those conductors which do not obey ohms law like tungsten

32
Q

Resistance

A

Property of material because of which it opposes and restricts free flow of charge

33
Q

Reason behind Resistance

A

Collisions of charged particles between free electrons and free electrons or collision with positive ions

34
Q

Factors affecting resistance

A

Temperature, Cross-sectional area, Length of wire, material of the wire

35
Q

How does cross-sectional area affect resistance?

A

Inversely proportional, as area increase, resistance decreases

36
Q

How does length of the wire affect the resistance?

A

Resistance is directly proportional to length as length increases, resistance also increase. This is because electrons travel, the more collisions they will have.

37
Q

What is resistivity?

A

Different materials offer different resistance because of a property, and that is resistivity. It converts the qualitative and uncertain data of temperature and material of resistor and converts it into measurable qualitative data

38
Q

Electrical power and si unit

A

Amount of electrical energy consumed per unit time
si unit = watt

39
Q

4 equations of electrical power

A

P = W/t (work done/time)
P = V * I (Voltage * current)
P = I^2 * R (Current^2 * resistance)
P = V^2/r (voltage^2/resistance)

40
Q

1 watt electric power

A

If 1 joule of electrical energy is consumed by a device in 1 second, the electric power of that device is said to be 1 watt

41
Q

Ideal ammeter value and why

A

0 ohms, since its in series with resistor, the current flowing wont be the same for ammeter and resistor and hence the ideal should be 0 ohms

42
Q

Ideal voltmeter value and why

A

Infinite ohms, to ensure that no current can flow in the ohmmeter since its parallel with the resistor

43
Q

Ammeter and voltmeter connected how? (in parallel or series)

A

Ammeter - Series
Voltmeter - Parallel

44
Q

Current flowing in series and parallel acorss resistors

A

Series = Same
Parallel = Not same as multiple paths for current to travel

45
Q

Potential difference in series and parallel across resistors

A

Series = Different
Parallel = Same and is equal to the voltage given by the power source

46
Q

Potential difference (V) formula

A

V = W/q
Work done/charge

47
Q

Charging body from neutral to -ve using conduction

A

Bring a negatuvely charged object in contact with a neutral object and the electrons from the negatively charged object will flow onto the neutral as the protons in the nuetral will atrract them

48
Q

Changing a body from neutral to +ve using conduction

A

Touch a +ve charged object with the neutral object attracting its electrons. Then electrons will flow onto the rod leaving the sphere with a positive charge.

49
Q

Why does a higher resistance mean a higher temperature being produced within the resistor?

A

Because more resistance means more collisions, and hence when the particles collide, they will release their kinetic energy in the form of heat energy to the atoms in the wire, and hence the resistance wire is heated. This is known as the heating effect of current

50
Q

Best resistor (ideal for heating effect of current)

A

Nickel, Tungsten

51
Q

RQ for coulombs law

A

How does changing the distance between 2 point charges affect its force of attraction/repulsion, keeping the charge present on both test charges and the medium of experiment constant throughout?

52
Q

RQ for heating effect of current

A

How does a change in the mass of (object/specific heat capacity) affect the time it takes for it to heat from 25° to 35°, keeping the power rating of the heating element constant throughout?

53
Q

RQ for series/parallel circuit

A

RQ: How does changing the number of resistors affect the current flowing in a series/parallel circuit for a constant voltage supplied, the resistance of the resistors, temperature, material, cross-sectional area, and length of the resistors?

54
Q

Hypothesis for Series circuit RQ

A

In a series circuit, adding more resistors increases the total resistance since the resistances sum up. According to Ohm’s Law, the total current ‘I’
is inversely proportional to the total resistance when the voltage ‘V’ is kept constant (I = V/R_total). Thus, as more resistors are added in series, the total resistance rises, resulting in a decrease in the current flowing through the circuit.

55
Q

Hypothesis for Parallel circuit RQ

A

For a Parallel Circuit:
In a parallel circuit, adding more resistors decreases the equivalent resistance because the reciprocal of the total resistance is the sum of the reciprocals of the individual resistances. Since the current total (I_total) is directly proportional to the voltage
divided by the net resistance (I_total = V/R_total). A decrease in net resistance due to additional resistors results in an increase in the total current generated by the circuit.

56
Q

How to find net resistance in a parallel combination of resistors

A

The reciprocal of the net resistance is the sum of the reciprocals of individuals resistors of the combination

57
Q

How does increasing the potential difference affect the current

A

The strength of the electric field increases as you see an increase in the potential difference. This causes electrons to get a stronger push from the -ve terminal due to like charges repelling and the electrons will have a higher attraction to the positive terminal

G9 + 10 physics (6 decks)

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