Brainscape's Knowledge GenomeTM

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


See full index

N5 Physics > Electricity > Flashcards

Electricity Flashcards

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

I know that there are two types of electrical charge

A

Positive
Negative

Like charges repel and unlike charges attract. The direction of the force on the charge will depend on the sign of the charge

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

I know the defination of electrical current

A

Electrical current is defined as the charge transferred (flowing) in a circuit per second

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

I can use the formula that relates charge, current and time

A

Q = I x t

Q = charge
I = current
t = time
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

I know the difference between direct current and alternating current

A

Alternating current (a.c.) is when current in a circuit continually changes direction. a.c. is supplied from the mains

Direct current _d.c.) is when the current flows in one direction only around a circuit. Batteries supply d.c. current

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

I know the effect of an electric field on a charge

A

Electric fields exist in the regions around electric charges. They can be reoresented by drawing field lines. The field is strongest when the field lines are closest together

Charged particles experience a force in an electrical field

On applying an electric field to a conductor for example, the free electric charges (electrons) experience a force and move

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

I know that the potential difference (voltage) of a supply is a measure of the energy given to the charge carriers in a circuit

A

A 12V battery gives 12J of energy to each coulomb of charge in a circuit

A 230V supply gives 230J of energy ti each coulomb of charge in a circuit

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

Cell

A

Sourceof electrical energy

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

Battery

A

Two or more cells joined together

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

Lamp

A

Changes electrical energy into light

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

Switch

A

Used to make a complete circuit

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

Resistor

A

Affects the current flowing in a circuit

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

Variable Resistor

A

Allows the current in a circuit to be changed

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

LED (light-emiting diode)

A

Changes electrical energy into light

uses less current than a lamp

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

Motor

A

Changes electrical energy into kenetic energy

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

Loudspeaker

A

Changes electrical energy into sound energy

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

Photovoltaic cell

A

Changes light energy into electrical

also known as a solar cell

17
Q

Fuse

A

Desgined to protect an appliance by melting if the current is too high

18
Q

Diode

A

Allows current to flow in one direction only

19
Q

Capacitor

A

Stores charge

20
Q

Thermistor

A

The resistance of a thermistor depends on temperature

21
Q

LDR (light dependent resistor)

A

The resistance of an LDR depends on light intensity

22
Q

NPN transistor

A

Acts as an electronic switch

23
Q

MOSFET transistor

A

Acts as an electronic switch

24
Q

I know an LED lights only when connected into a circuit the correct way around

A

An LED is made up of two special materials called semiconductors joined together
For an LED to light the positive terminal of the LED must be connected to the positive terminal of the power supply
LEDs come in colours of red, green, yellow, blue and white
For a correctly connected LED to light up the voltage accross the LED must be above the “switching on” voltage for that LED
As soon as this voltage is reached the LED switches on, thereafter increasing the voltage across the LED will increase the brightness of the LED

25
Q

I know why an LED always has a resistor connected in series with it

A

An LED will brake if too high a current passes through it or if there is too high a voltage across it. To prevent this an LED must always be connected in series with a protective resistor

26
Q

I know the current and voltage relationships in a series circuit

A

In a series circuit the battery/power supply and circuit components are connected in a continuous loop

There is only one path for current in a series circuit and so the current is the same at all points
Isupply = I1 = I2 = I3 = …

The sum of all the voltages across components in series is equal to the supply voltage
Vsupply = V1 + V2 + V3 + …

27
Q

I know the current and voltage relationships in a parallel circuit

A

In a parallel circuit there are many paths around the circuit

The current in the individual paths add up to the current in the main circuit
Isupply = I1 +I2 + I3 + …

The voltages across the comonents in the circuit are the same
Vsupply = V1 = V2 = V3 = …

28
Q

I can use the appropriat eformula to calculate resistance in a series circuit

A

RT = R1 + R2 + R3 + …

RT = Total Resistance of the circuit (measured in ohms)
R1 = Resistance of component 1 (measured in ohms)
R2 = Resistance of component 2 (measured in ohms)
R3 = Resistance of component 3 (measured in ohms)
When resistors are combined in series the total resistance increaces

29
Q

I can use the appropriate formula to calculate resistance in a parallel circuit

A

1/RT = 1/R1 + 1/R2 + 1/R3 + …

R1 = Resistance of component 1 (measured in ohms)
R2 = Resistance of component 2 (measured in ohms)
R3 = Resistance of component 3
When resistors are combined in para;;e; tje tpta; resostamce decreases

30
Q

I can use a V - I graph to determine resistance

A

Using the following circuit a sample set of results can be generated to plot a V - I graph

  • The graph shows that as the voltage across the component increases, the current through the component also increases
  • The graph also shows the link between Voltage and Current
  • The cradient of the graph can be found for any point by dividing V/I
  • For the graph above the gradient is constated
  • This constant is called the resistance of the component
31
Q

i can use the formula that relates voltage, current and resistance

A

V = I x R

V = Voltage (measured in volts, V)
R = Current (measured in amperes, A)
R = Resistance (measured in ohms)
32
Q

I know that a transistor can be used as a switch

A

Transistors can be thought of as electronic switches which have no moving parts The following are two examples of a transistor:

  • n-channel MOSFET
  • npn - transistor

When the voltage across a trajsistor reaches a certain value called the switching on voltage the transistor switches on. When the voltage across the trainsistor drops below this value the transistor switches off
Different types of transistor have different switching on voltages

33
Q

I know the relationship between temperature and resistance of a conductor

A

As the temperature of a conductor increases its resistance increases

When a conductor is heated, the atoms vibrate with grater amplitude. This makes it more difficult for electrons to move through the material

N5 Physics (1 decks)

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