•  Materials that are electrical conductors conduct charge easily – a current can flow through them. They’re usually metals, e.g. copper and silver
•  Electrical insulators don’t conduct charge very well – so a current can’t flow. Examples include plastic and rubber

1)     With a polythene rod, electrons are transferred from the duster to the rod, leaving it negatively charged. When a metal strap is connected to a negatively charged object and the earth to be earthed, electrons flow from the object down to the ground.

2)     With an acetate rod, electrons are transferred from the rod to the duster, leaving it positively charged. When it is earthed, a metal strap is connected to the object and the ground, and electrons flow up the strap from the earth

• The greater the charge on an isolated object, the greater the voltage between it and the Earth. If the voltage gets big enough, there’s a spark which jumps across the gap

GOLD-LEAF ELECTROSCOPE

1)     A gold-leaf electroscope has a metal disc connected to a…