K.C.S.E Physics Q & A - MODEL 1997PP2QN06

K.C.S.E Physics Q & A - MODEL 1997PP2QN06

(a) (i) Distinguish between semiconductor and conductors
(ii) Give one example of a semiconductor and one for a conductor
(b) An npn transistor is operating in the common emitter mode
(i) Draw the circuit diagram and indicate the direction of the currents
(ii) Given that the emitter current is 2.0 m A and that 0.5% of the electrons diffusing into the base combine there with holes, determine the values of the base current and the collector current
(ii) By increasing the p.d across the emitter – base junction in (ii), the emitter current increase to 4mA. Determine the transistor current amplificatio

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