State whether the following are good conductors, poor conductors or insulators:

Water

An electric cell has _____ terminals.

A device which is used to 'make' or 'break' an electric circuit is called _____.

Electricity flows in a/an _____ (closed/open) circuit.

The part of the torch bulb that gives off light is the _____. (Metallic base/Filament)

An electric circuit containing a cell and a torch bulb is connected by using the following objects turn by turn:

Matchstick, Iron nail, Eraser, Glass bangle, Key

Which of the above will make the bulb glow and which will not? Give reasons for your answer.

What is the purpose of using an electric switch? Name some electrical gadgets (electrical appliances) which have switches built into them.