P3.2.5 - LDRs And Thermistors Flashcards
1
Q
What is a thermistor?
A
It’s resistance depends on temperature
2
Q
What is a thermistor made of?
A
A semiconducting material such as silicon
3
Q
What are the characteristics of a semi conductor?
A
The electrons in their atoms do not need much energy to escape and form a current
4
Q
Why does the resistance of a thermistor change with temperature?
A
As you heat the thermistor many electron gain enough energy to escape the atoms of the semiconductor
5
Q
What is the resistance of thermistors at high and low temperatures?
A
Low temp = small current = high resistance
High temp = high current = low resistance
6
Q
What is an LDR?
A
Light dependent resistor
It’s resistance changes with light intensity
Light causes electrons to be released
