Basic Electronics Paper 2, WASSCE (PC 2ND), 2021

Question 5

 

  1. Figure 3 is the diagram of a non-inverting operational amplifier.
  2.  

    If the voltage gain of the amplifier is 21, calculate the value of R1.

  3. State four applications of operational amplifier.

The expected responses were:

 

(a)                                                                                                  
(b)        Applications of operational amplifier

  • Filter circuit
  • Electrocardiogram amplification
  • Differentiator
  • Integrator
  • Summing circuit
  • Strain gauge
  • Piezoelectric transducer
  • Comparator
  • Voltage follower
  • Inverting and non-inverting amplification

The Chief Examiner reported that majority of the candidates that attempted this question responded did not do quite well with their response to the tasks.