Conductivity in semiconductors
Answers are for parents and teachers.
1
If 4·10⁶ arsenic atoms are added to silicon, how many free electrons form (one each)?
4000000
2
A thermistor has 600 Ω at 20 °C and 150 Ω at 60 °C. By what factor did the resistance fall?
4
3
Silicon doped with boron (3 valence electrons) is of which type?
p-type
4
Why does the conductivity of a semiconductor grow when light falls on it?
Light energy breaks bonds, creating more free electrons and holes.
5
Give an example of the use of a semiconductor thermistor or photoresistor.
A thermistor – a temperature sensor; a photoresistor – a light-sensitive automatic lamp.