What are LDRs and thermistors?
LDRs are used as light sensors. THERMISTOR. This is a type of resistor which has a resistance that changes with TEMPERATURE. The increasing temperature produces more free electrons and so the resistance falls.
Where can LDRs and thermistors be used?
Thermistors and LDRs
- Thermistors are used as temperature sensors, for example, in fire alarms.
- At low temperatures, the resistance of a thermistor is high, and little current can flow through them.
- At high temperatures, the resistance of a thermistor is low, and more current can flow through them.
What are LDRs used for?
LDRs (light-dependent resistors) are used to detect light levels, for example, in automatic security lights. Their resistance decreases as the light intensity increases: in the dark and at low light levels, the resistance of an LDR is high and little current can flow through it.
What happens with LDR and thermistor?
the resistance of an LDR varies with light intensity, the resistance of a thermistor varies with temperature, and these properties used in sensing systems to monitor changes in the environment.
What does mean LDRs?
Informal. long-distance relationship: a relationship, typically a romantic one, in which the two people live far enough apart that they cannot see each other often: My boyfriend and I had an LDR for two years.
What are LDRs made of?
As its name implies, the Light Dependent Resistor (LDR) is made from a piece of exposed semiconductor material such as cadmium sulphide that changes its electrical resistance from several thousand Ohms in the dark to only a few hundred Ohms when light falls upon it by creating hole-electron pairs in the material.
What is the relationship between temperature and resistance for a thermistor?
When temperature increases, the resistance increases, and when temperature decreases, resistance decreases. This type of thermistor is generally used as a fuse.
What is the output of LDR sensor?
The LDR gives out an analog voltage when connected to VCC (5V), which varies in magnitude in direct proportion to the input light intensity on it. That is, the greater the intensity of light, the greater the corresponding voltage from the LDR will be.