A conductor is a material that allows charge (usually electrons) to flow through it easily. Conductors tend to be metals .

An insulator is a material that has no free charges , so does not allow the flow of charge through it very easily.

Name four examples of conductors .

Silver , copper , aluminium and steel .

Name four examples of insulators .

Rubber , plastic , glass and wood .

On an atomic scale, why do metals conduct electricity so well?

Metals consist of positively charged metal ions with their outermost electrons delocalised (free to move). Since current is the rate of flow of electrons, the more easily electrons can move, the better the conductor.

In a conductor, the outermost electrons of the metal ions are ______ , meaning they are free to move.

In a conductor, the outermost electrons of the metal ions are delocalised , meaning they are free to move.

True or False? Insulators such as wood never conduct any charge at all.

False. Some non-metals, such as wood , allow a little charge to pass through them in the form of static electricity, even though they are not good conductors.

What is the aim of the core practical investigating charging by friction?

To investigate how insulating materials can be charged by friction.

In this investigation, what are the independent and dependent variables?

Independent variable : the material of the test rod. Dependent variable : the charge on the rod, observed via the motion of the suspended polythene rod.

State three control variables for this experiment.

Time spent rubbing the rod, using the same type of cloth, and using the same length of rod.

If a test rod rotates away from (is repelled by) the suspended polythene rod, what does this indicate?

The two rods have the same (like) charge.

If a test rod moves towards (is attracted to) the suspended polythene rod, what does this indicate?

The two rods have opposite charges.

If the ends of the two rods touch during the experiment, the rods will ______ and the forces will no longer be present.

If the ends of the two rods touch during the experiment, the rods will discharge and the forces will no longer be present.

Why must this experiment be carried out in a draught-free room, on a table free from vibrations?

Draughts or vibrations could affect the motion of the suspended polythene rod, introducing a random error into the observations.

True or False? A polythene rod becomes positively charged when rubbed with a cloth.

False. A polythene rod becomes negatively charged, because electrons are transferred to the rod from the cloth.

Define static electricity .

Static electricity is the accumulation of charge on an object, which can then attract other objects or produce sparks.

Define non-contact force .

A non-contact force is a force that acts on an object without the objects being physically in contact with each other, such as the electric force between two charged objects.

What determines whether two charged objects attract or repel each other?

Like charges (both positive or both negative) repel ; opposite charges (one positive, one negative) attract .

How does the distance between two charged objects affect the electric force between them?

The force is stronger when the objects are closer together .

Why is the overall charge of a neutral atom zero?

A neutral atom contains an equal number of protons (positive) and electrons (negative), so the equal but opposite charges cancel out.

Charging by friction occurs when negatively charged ______ are transferred from one insulating material to another.

Charging by friction occurs when negatively charged electrons are transferred from one insulating material to another.

In charging by friction, which object becomes negatively charged and which becomes positively charged?

The object that electrons transfer to becomes negatively charged. The object that electrons transfer from becomes positively charged.

True or False? When charging by friction, positive charge moves from one insulator to the other.

False. Only electrons (negative charge) move during charging by friction; an object that loses electrons is left with an equal positive charge.

How does a photocopier use static electricity to copy a document?

An image is projected onto a positively charged copying plate, which loses charge in light areas but keeps positive charge in dark (text) areas. Negatively charged toner powder sticks to the positively charged areas and is transferred to paper, which is heated to fix the toner.

Why is insecticide given an electrostatic charge as it leaves a sprayer?

The charged droplets repel each other (same charge), keeping the spray fine and spread over a large area. They are also attracted to the Earth's opposite charge, so they fall quickly and are less likely to blow away.

Earthing is connecting an object (e.g. a vehicle) to the Earth using a conductor, allowing a build-up of charge to flow away safely instead of causing a spark.

Why is a build-up of static charge dangerous when refuelling an aeroplane?

Friction between the flammable fuel (an insulator) and the pipe causes the fuel to gain charge . If this charge produced a spark, the fuel could ignite and cause an explosion.

How does the bonding line reduce the risk of sparking when refuelling an aeroplane?

The bonding line is a copper wire connecting the fuel tank to the Earth. It is easier for charge to flow down the bonding line than to spark, so it carries the charge away and removes the risk of sparks.

Define a spark , in the context of static hazards.

A spark is current travelling through the air between two objects, caused when a large build-up of charge produces a potential difference across a gap that is large enough to break down the air.

In an inkjet printer, a small jet of coloured ink is ______ charged and attracted to the correct place on the page.

In an inkjet printer, a small jet of coloured ink is negatively charged and attracted to the correct place on the page.

True or False? Static electricity is only ever dangerous, with no everyday practical uses.

False. Static electricity is put to practical use in photocopiers , inkjet printers and insecticide sprayers , as well as posing dangers such as sparking.

IGCSEPhysicsEdexcelPhysics (Modular)Unit 1Flashcards2. ElectricityStatic Electricity

Static Electricity (Edexcel IGCSE Physics (Modular): Unit 1): Flashcards

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Cards in this collection (31)

Define conductor.
A conductor is a material that allows charge (usually electrons) to flow through it easily. Conductors tend to be metals.
Define insulator.
An insulator is a material that has no free charges, so does not allow the flow of charge through it very easily.
Name four examples of conductors.
Silver, copper, aluminium and steel.
Name four examples of insulators.
Rubber, plastic, glass and wood.
On an atomic scale, why do metals conduct electricity so well?
Metals consist of positively charged metal ions with their outermost electrons delocalised (free to move). Since current is the rate of flow of electrons, the more easily electrons can move, the better the conductor.
In a conductor, the outermost electrons of the metal ions are ______, meaning they are free to move.
In a conductor, the outermost electrons of the metal ions are delocalised, meaning they are free to move.
True or False?
Insulators such as wood never conduct any charge at all.
False.
Some non-metals, such as wood, allow a little charge to pass through them in the form of static electricity, even though they are not good conductors.
What is the aim of the core practical investigating charging by friction?
To investigate how insulating materials can be charged by friction.
In this investigation, what are the independent and dependent variables?
Independent variable: the material of the test rod. Dependent variable: the charge on the rod, observed via the motion of the suspended polythene rod.
State three control variables for this experiment.
Time spent rubbing the rod, using the same type of cloth, and using the same length of rod.
If a test rod rotates away from (is repelled by) the suspended polythene rod, what does this indicate?
The two rods have the same (like) charge.
If a test rod moves towards (is attracted to) the suspended polythene rod, what does this indicate?
The two rods have opposite charges.
If the ends of the two rods touch during the experiment, the rods will ______ and the forces will no longer be present.
If the ends of the two rods touch during the experiment, the rods will discharge and the forces will no longer be present.
Why must this experiment be carried out in a draught-free room, on a table free from vibrations?
Draughts or vibrations could affect the motion of the suspended polythene rod, introducing a random error into the observations.
True or False?
A polythene rod becomes positively charged when rubbed with a cloth.
False.
A polythene rod becomes negatively charged, because electrons are transferred to the rod from the cloth.
Define static electricity.
Static electricity is the accumulation of charge on an object, which can then attract other objects or produce sparks.
Define non-contact force.
A non-contact force is a force that acts on an object without the objects being physically in contact with each other, such as the electric force between two charged objects.
What determines whether two charged objects attract or repel each other?
Like charges (both positive or both negative) repel; opposite charges (one positive, one negative) attract.
How does the distance between two charged objects affect the electric force between them?
The force is stronger when the objects are closer together.
Why is the overall charge of a neutral atom zero?
A neutral atom contains an equal number of protons (positive) and electrons (negative), so the equal but opposite charges cancel out.
Charging by friction occurs when negatively charged ______ are transferred from one insulating material to another.
Charging by friction occurs when negatively charged electrons are transferred from one insulating material to another.
In charging by friction, which object becomes negatively charged and which becomes positively charged?
The object that electrons transfer to becomes negatively charged. The object that electrons transfer from becomes positively charged.
True or False?
When charging by friction, positive charge moves from one insulator to the other.
False.
Only electrons (negative charge) move during charging by friction; an object that loses electrons is left with an equal positive charge.
How does a photocopier use static electricity to copy a document?
An image is projected onto a positively charged copying plate, which loses charge in light areas but keeps positive charge in dark (text) areas. Negatively charged toner powder sticks to the positively charged areas and is transferred to paper, which is heated to fix the toner.
Why is insecticide given an electrostatic charge as it leaves a sprayer?
The charged droplets repel each other (same charge), keeping the spray fine and spread over a large area. They are also attracted to the Earth's opposite charge, so they fall quickly and are less likely to blow away.
Define earthing.
Earthing is connecting an object (e.g. a vehicle) to the Earth using a conductor, allowing a build-up of charge to flow away safely instead of causing a spark.
Why is a build-up of static charge dangerous when refuelling an aeroplane?
Friction between the flammable fuel (an insulator) and the pipe causes the fuel to gain charge. If this charge produced a spark, the fuel could ignite and cause an explosion.
How does the bonding line reduce the risk of sparking when refuelling an aeroplane?
The bonding line is a copper wire connecting the fuel tank to the Earth. It is easier for charge to flow down the bonding line than to spark, so it carries the charge away and removes the risk of sparks.
Define a spark, in the context of static hazards.
A spark is current travelling through the air between two objects, caused when a large build-up of charge produces a potential difference across a gap that is large enough to break down the air.
In an inkjet printer, a small jet of coloured ink is ______ charged and attracted to the correct place on the page.
In an inkjet printer, a small jet of coloured ink is negatively charged and attracted to the correct place on the page.
True or False?
Static electricity is only ever dangerous, with no everyday practical uses.
False.
Static electricity is put to practical use in photocopiers, inkjet printers and insecticide sprayers, as well as posing dangers such as sparking.

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