7J Electrical Circuits Flashcards
What do large appliances in your house use
Mains electricity
Smaller items use
Cells (batteries)
What is an electric current
A flow of electrons
What is a circuit
A complete loop that an electric current can flow through
What is the current
The amount of electricity that is flowing around a circuit
What does current do
Carry energy to the components
The larger the current the …..
Brighter the bulb
How do we measure current and what is the unit of measurement
We measure using an ammeter
Amps(A)
Does current get used up
No it is the same everywhere
Components which have a high resistance
Make it difficult for current to flow
How do we make the current smaller
We make that current smaller by using a resistor
The higher the voltage
The bigger the current
How do we make bigger currents
By putting more cells together
What is produced by electricity and is it useful
Heat is useful
H9w does a light bulb give out l8ghg
The filament ( piece of wire in the middle) has a high resistance so when a current flows through it gets so hot it glows
What is a fuss and what does it do
It is a piece of wire that is designed to melt if the current gets to big
It melts so no current can flow ( it breaks the circuit )
What are all materials made of ? Hint tiny particles
Atoms
Atoms have smaller particles called what in them
Electrons
Why are metals conductors
Because electrons can move easily inside them
What is a series circuit
A circuit with all components in one loop . If one bulb breaks they all break
What is a parallel circuit
Has a lot of branches . If one bulb breaks the others still work
Does the current split up in an series circuit or a parallel
Parallel
Symbol for cell , lightbulb , ammeter and switch , motor , buzzer
Cell- one long line and one dark thick short line with a space in the middle
Lightbulb - circle with a x in it
Ammeter - a circle with a capital A
Switch - a small circle a line which will be up if it is off and a circle at the beginning of th wire
Motor - circle with motor
Buzzer - like a bowl on a stand
What do we call electrical signals sent by the brain and what do they travel by
Impulses and nerves
What can an electric shosck do
Burn the skin or stop the nerves from working properly
What measure of current can kill a human
0.070A
What happens when your skin is wet
It has a lower resistance so a much higher current
What does a cell do
Acts like a pump - provides the force to push the charge around - it is called potential difference
To calculate total potential difference in a circuit
You add up the potential difference from all the batteries
Resistance formula
Potential difference divided by current
What is potential difference
The driving force a battery provides
