2 4 static electricity

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

Three good conductors are:

Three good insulators are:

False. Static charge is able to build up on insulators when rubbed with another insulating material.

The independent variable is the material of the rods being charged.

The dependent variable is the charge on the rod.

Hanging the rods from strings suspends them, allowing them to move freely when subjected to a force. Their charge can be deduced from this movement.

True. The rods repel because they have the same charge, causing them to move apart.

Two random errors may be:

The purpose of rubbing insulating solids with a cloth in electrostatic experiments is to transfer electrons between the cloth and the insulator, leaving the rod with a net charge.

Static electricity is the build-up of charge on an object, this can be either an excess of positive charge or negative charge.

When certain insulating materials are rubbed against each other they become electrically charged

False. When an object becomes positively charged through charging by friction, this is because it loses electrons, not because it has gained positive charge.

Two insulators become charged when rubbed together because electrons are transferred between them. One insulator gains electrons and the other loses electrons.

The force between two opposite charges is attractive.

The force between two similar charges is repulsive.

An insulator becomes negatively charged when electrons are transferred to it.

A potential danger of static electricity is

Sparking occurs when

When refuelling a plane, the risk of sparking can be reduced by connecting the fuel tank to the Earth (using a bonding line) to carry excess charge away.

Two common uses of static electricity are:

The paint droplets are all given the same charge so they repel and spread out.

False. Negatively charged black toner particles are attracted to positive regions of paper in a photocopier.