The electrical conductively of pure germanium can be increased by
A. increasing the temperature
B. doping acceptor impurities
C. doping donor impurities
D. irradiating ultraviolet light on it.
Increasing the temperature increases the breaking of the covalent bonds and generation of more electron-hole pairs. Thus, increasing the conductivity.
For B and C
Since doping will increase the no. of charge carriers, therefore the conductivity will increase.
Irradiating UV light on germanium will provide energy enough to break the covalent bond and thus create an electron-hole pair. Thus increasing the electrical conductivity.
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