The expected responses were:

(a)        A transducer is defined as a device that converts energy from one form into another.

(b)        Energy transformation in transducers      

(i) Tachogenerator: converts angular speed (or velocity-mechanical energy) into voltage (electrical energy).

(ii) Piezo-electric crystal: converts mechanical strain (or pressure-mechanical energy) into voltage electrical energy)

(iii) Photo-voltaic cell: converts light energy into electrical energy

(iv) Loudspeaker : converts electrical energy into sound (mechanical energy)

(v) Phono graphic pick-up needle: converts mechanical vibrations into sound energy

(vi) (Electric) Motors: converts electrical energy into mechanical energy. (Vehicular motors essentially convert chemical energy into mechanical energy.

(vii) Thermocouples: converts temperature difference (heat energy) into voltage (electrical energy)

(viii) Microphones: converts sound energy into electrical energy.

The Chief Examiner reported that, overall, majority of the candidates that attempted this question responded well while only a few could not state the energy transformation that exist in piezo-electric crystal and phonographic pick-up.