Question
A student sets up this circuit.
What is the purpose of the circuit?
to allow a lamp to be made dimmer or brighter as required
to amplify the sound of a voice
to light a lamp in the dark
to sound a bell when the temperature rises
Answer/Explanation
Ans: D
Question
An air-conditioning unit, a lamp and an electric fire all receive electrical energy from the mains supply.
From which of these devices is all this energy eventually transferred to the surroundings?
Answer/Explanation
Ans: A