(i) Name an instrument that measures electric current in a circuit. Define unit of electric current.
An instrument that measures electric current in a circuit is an Ammeter.
The current is said to be one ampere if 1 coulomb of charge flows through a cross section of conductor per second.
(ii) What are the following symbols mean in an electric circuit.
- Closed plug key
(iii) Draw a closed circuit diagram consisting of 0.5 m long nichrome wire XY, an ammeter, a voltmeter, four cells of 1.5 V and a plug key.