AQA GCSE Physics - Electricity

What is the circuit symbol for an ammeter?

What is the circuit symbol for a battery?

What is the circuit symbol for a cell?

What is the circuit symbol for a diode?

What is the circuit symbol for a fuse?

What is the circuit symbol for a lamp (bulb)?

What is the circuit symbol for an LDR?

What does LDR stand for?

Light dependent resistor

What is the circuit symbol for an LED?

What is the circuit symbol for a resistor?

What is the circuit symbol for a closed switch?

What is the circuit symbol for an open switch?

What is the circuit symbol for a thermistor?

What is the circuit symbol for a variable resistor?

What is the circuit symbol for a voltmeter?

For electrical charge to flow through a closed circuit the circuit must include a source of _________ __________

Potential Difference

Electric current is a flow of electrical ______

Charge

The size of an electric _______ is the rate of flow of electrical charge

current

What is the equation for charge?

current x time

Unit of charge flow, Q

coulombs, C

Unit of current, I

amps, A

Unit of time, t

s

Current has the same value at any point in a ______ circuit

series

The current (I) through a component depends on both the __________ of the component and the potential difference (V) across the component

Resistance (R)

For a given potential difference (voltage), the greater the resistance of the component the smaller the _______

current

What is the equation for potential difference?

potential difference = current x resistance

Unit of potential difference, V

volts, V

Unit of resistance, R

ohms, Ω

The current through an ohmic conductor (at constant temperature) is ________ ____________ to the potential difference across the resistor.

directly proportional

The resistance of components such as lamps, diodes, thermistors and LDRs is not constant; it changes with the _______ through the component

current

The resistance of a filament lamp increases as the ___________ of the filament increases

temperature

The current through a diode flows in ___ _________ only

one direction

The _____ has a very high resistance in the reverse direction

diode

The resistance of a __________ decreases as the temperature increases

thermistor

The resistance of an LDR decreases as _____ _________ increases

light intensity

An ___ can be used to switch lights on when it gets dark

LDR

A __________ can be used to switch heaters on when it gets cold

thermistor

There are two ways of joining electrical components, in series and in ________

parallel

For components connected in series there is the same _______ through each component

current

For components connected in series the total potential difference of the power supply is ______ between the components

shared

For components connected in series the total __________ of two or more components is the sum of the __________ of each component

resistance

For components connected in parallel the potential difference across each component is...

the same

For components connected in parallel the total _______ through the whole circuit is the sum of the _______ through the separate branches

current

For components connected in parallel the total resistance of two or more resistors is ____ ____ the resistance of the smallest individual resistor

less than

Mains electricity uses __________ ______

alternating current

In a series circuit, components are connected in...

one loop

The alternating current used in UK mains electricity has a frequency of ____

50Hz

In a parallel circuit, components are connected in...

more than one loop

The potential difference of UK mains electricity is about ___ Volts

230

Most electrical appliances are connected to the mains using _____-____ _____

three-core cable

The _____ wire carries the alternating potential difference from the supply

live

The ______ wire completes the circuit

neutral

Direct potential difference induces current to...

flow in one direction

The ______ wire is a safety wire to stop the appliance becoming live

earth

Alternating potential difference induces current to...

alternate the direction of flow

The potential difference between the live wire and earth is about ___ Volts

230

The potential difference across the neutral wire is at, or close to ___ Volts

0

The colour of the insulation covering the LIVE wire is...

brown

For a given resistance, as the potential difference across a device increases, the _______ through a device will also increase

current

The colour of the insulation covering the NEUTRAL wire is...

blue

If the current through a device increases, the amount of ______ transferred per second (power) will also increase

energy

The colour of the insulation covering the EARTH wire is...

green & yellow

Power of-, potential difference across- and current through a device are linked by the equation

power= potential difference x current

Power & resistance of a device, and current through a device are linked by the equation

Current² x Resistance

Unit of power, P

watts, W

Everyday electrical appliances are designed to bring about ______ transfers

energy

If an appliance becomes live a person could experience an...

electric shock

The amount of ______ an appliance transfers depends on how long the appliance is switched on for and the power of the appliance

energy

____ is done when charge flows in a circuit

Work

Equation for energy transferred?

power x time

The _____ wire is at 0 Volts, it only carries a current if there is a fault

earth

What is the equation for energy transferred?

charge flow x potential difference

Unit of energy transferred, E

joules, J

A more powerful device will transfer energy ______ than a less powerful one

quicker

The ________ ____ is a system of cables and transformers linking power stations to consumers

National Grid

Electrical _____ is transferred from power stations to consumers using the National Grid

power

Step-up transformers are used to ________ the potential difference from the power station to the transmission cables

increase

Step-down transformers are used to ________, to a safe value, the potential difference for domestic use

decrease

Step-up transformers dramatically decrease the _______ flowing in the transmission cables

current

Less current flowing in the transmission cables means less _____ lost due to heating effects

power

Less power lost in the transmission cables means the National Grid is more _________

efficient

When certain __________ are rubbed against each other they become electrically charged

insulators

When two insulating materials experience friction negatively charged _________ transfer from one insulator to the other

electrons

Insulators that transfer electrons to another insulator become __________ charged

positively

Insulators that gain electrons from another insulator become __________ charged

negatively

When two electrically charged objects are brought close together they exert a _____ on each other

force

Two objects that carry the same type of charge will _____ when brought close together

repel

Two objects that carry different types of charge will _______ when brought close together

attract

Attraction and repulsion between two charged objects are examples of ___-_______ force

non-contact

A charged object creates an ________ _____ around itself

electric field

The electric field is _________ close to the charged object

strongest

The further away from the charged object, the ______ the electric field

weaker

A second charged object placed in an electric field experiences a _____

force

The force between two charged objects gets stronger as the distance between the objects _________

decreases

The field lines around a negatively charged sphere radiate _______ the centre

towards

The field lines around a positively charged sphere radiate _______ from the centre

outwards