Question 5
- Fig 2 is the diagram of a series RLC circuit
(i) state one condition for the circuit in Fig. 2 to be at resonance.
(ii) If the circuit is at resonanmce, show that
(i)
(ii)
Fig 3. Is the block diagram of a simple audio system
- Identify the parts labelled w,x and y
- State the energy conversion effected by each of w and y
- State the function of x in the operation of the system
- Name one electronic communication system that employs the model in fig 3
Observation
The expected responses were
(b)
W – microphone
X – amplifier/ audio amplifier
Y – Speaker / Loud speaker
(i)
Energy conversion effected by
W – sound energy to electrical energy
Y - electrical energy to sound energy
(ii)
Function of X in the operation of the system
It amplifies/ boosts the amplitude of electrical signal
(iii)
Public address system, Radio receiver, TV receiver
The chief examiner reported that question 5 was unpopular among candidates as only a few of them attempted it and did well in the question.