Topic 2 - LDRs, Thermistors and LEDs Flashcards
1
Q
what is a light-emitting diode (LED)?
A
they emit light when a current flows through them in a forward direction
2
Q
what is the difference between a LED and a light bulb?
A
light bulbs have a filament that can burn out
3
Q
what is a light-dependent resistor (LDR)?
A
a type of resistor that changes its resistance depending on how much light falls on it
4
Q
what is a thermistor?
A
a temperature-dependent resistor
5
Q
what happens to LDRs as light becomes brighter?
A
resistance falls
6
Q
what happens to thermistors in hot conditions?
A
resistance drops
