waecE-LEARNING
Electronics Paper 2, May/June 2012  
Questions: 1 2 3 4 5, 6 &7 8 9 10 Main
General Comments
Weakness/Remedies
Strength
















Question 1
  1. Sketch and label the circuit symbol for each of the following devices:
    1. n- channel junction field effect transistor;
    2. thyristor;
    3. triac.
  2.   State one application each of the devices in (a).
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OBSERVATION

The expected answers were:
          (a)              

 

(b)      Applications:

          (i)      n-channel                            (ii)      Thyristor                (iii)     Triac
                   -  Input amplifier                          -  power control               -  Relay control
                   -  Logic circuits                              device                               -  Motor control
                    -  Large scale integration          - Switch control                -  Phase control
                                                                                                                        -  Inverters
                                                                                                                        -  Heater control    
                                                                                                                        -  Static switches

The question was on Semiconductor Devices. It was quite popular with the candidates. The performance was very good.
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