Electricity Flashcards
How do objects become charged?
By friction – rubbing a balloon against your jumper or a rod with a cloth
What do we mean by charge?
Charge is a property of particles, just as size is a property of particles.
How do charged objects behave?
Similarly charged objects repel, oppositely charged objects attract.
How do charges interact?
They can repel or attract each other
What is an electric field?
The space around a charged object where another charged object feels a force of attraction or repulsion.
How can we make large amounts of charge?
We can use a machine called a Van De Graaf generator.
How are large amounts of charge made naturally?
When rain clouds pass past each other.
What is the danger of high amounts of charge?
High amount of charge can cause electric shocks.
How do we make large amounts of charge safe?
We ‘Earth’ object so they take the charge to the ground.
What do we mean by the conduction of charge?
When charges can flow through materials.
What do we mean by insulators?
Materials that do not let charge flow through them.
What kind of materials are conductors and insulators?
Metals are good conductors of charge and plastics or rubber are good insulators.
In electricity, what do we mean by components?
Any simple electrical device is called a component.
How do we represent circuit components?
We use symbols to represent components.
How do we represent circuits where components are connected up?
We use circuit diagrams.
What is a complete circuit?
When there is an unbroken route from one component to the next and back to the first.
How do we draw circuits?
We use circuit diagrams
What is electric current?
Current is a flow of electric charge
What is potential difference?
Potential difference is the ‘push’ that make charges flow.
What does current do when it passes through conductors and components?
Current shifts energy from one component to another.
How can we model current, potential difference and and resistance in a circuit?
The Water Heater Model and the Rope Model,
How do we measure current?
We measure current with an ammeter.
What is the unit of current?
The unit of current is Amperes (or Amps for short).
What is the unit of potential difference?
The unit of potential difference is the Volt
What happens to current as it passes around a circuit?
The current shifts energy, it is not charged.
What is the difference between a series and a parallel circuit?
A series circuit has only one pathway or loop back to the cells, a parallel circuit has more than one pathway.
How do bulbs behave in a series circuit?
In a series circuit adding another bulb will cause both bulbs to become dimmer and if one bulb is broken the other does not light up.
How do bulbs behave in a parallel circuit?
In a parallel circuit adding another bulb will cause both bulbs to light up the same as before and if one bulb is broken the other bulb carries on as normal.
What happens to current as it travels around a circuit?
The current shifts energy but it is not used up.
How does the current behave in a series circuit where there is only one pathway?
The current is the same in every part of the circuit.
What happens to current in a parallel circuit where there are two pathways?
The current in each pathway adds up to the current coming from or returning to the cell/battery.
What is an electric plug used for?
To supply electricity to electrical devices.
What materials is it made from and why?
Plastic casing because it is an insulator and brass pins because it is a conductor.
What does it have inside and why?
2 or 3 wires with the outside made of plastic insulator, covering copper wire, a conductor.
What is the job of the Earth wire in a plug?
To make the electrical device safe in case of a fault.
What is the job of a fuse in a plug?
To prevent wire from overheating and causing a fire.
What is a fuse wire?
A very thin piece of conducting metal wire that can take a certain amount of current.
What happens if too much current flows through a fuse wire?
If too much current flows through a fuse wire it get so hot that it melts.
