Current and voltage. Flashcards
What way does a current flow?
From negative to positive.
What is a current?
A measure of how many electrons flow through a certain point in one second.
How is a current measured?
It is measured using a device called an ammeter.
What is the abbreviation for Amps?
It is simply (A).
Where are ammeters placed in a circuit?
it is placed in a series circuit to measure the charge flowing through it.
What is Voltage?
A measure of how much energy is being used at a given time. It is the potential difference.
Why is voltage called potential difference?
Because the charge is between two points.
How is voltage measured between two points?
it is measured with a voltmeter and it is abbreviated as volts (V).
Where must volt meters be placed?
They must be placed in parallel with the components for the voltage to be measured.
What happens to the current and voltage in a series circuit?
The current stays the same, but the voltage is shared with each load. If more components are added the light becomes dimmer on each one.
What happens to the current and voltage in a parallel circuit?
The current is shared, but the voltage stays the same.
What happens when a bulb blow in a series circuit?
All of the bulbs will stop working, as no current will flow through them as there is a gap in the circuit.
What happens when more devices are connected to a parallel circuit?
The current flowing through the batteries and cells increases.
What are fuses and fuseboxes?
They are devices that are used to help prevent the wire from over loading. This stops the wire giving someone an electric shock or starting a fire.
What is resistance?
The ‘difficulty’ that electrons have moving through a device.
