How does a thermistor work GCSE?
How does a thermistor work GCSE?
The thermistor Their resistance decreases as the temperature increases. 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.
How does thermistor work?
A thermistor is a resistance thermometer, or a resistor whose resistance is dependent on temperature. When temperature increases, the resistance increases, and when temperature decreases, resistance decreases. This type of thermistor is generally used as a fuse.
What is a thermistor GCSE physics?
Thermistor. Thermistors are used as temperature sensors, for example, in fire alarms. In the most common type of thermistor, the resistance decreases as the temperature increases: at low temperatures, the resistance of a thermistor is high and little current can flow through them.
How does a thermistor work a level?
A thermistor is resistor which has a resistance that changes with temperature. Increasing the temperature frees more electrons to carry the current and so the resistance falls. Very little current will flow through the thermistor when the circuit is cold. It therefore can be made to work like a switch in a circuit.
What is a thermistor for kids?
A thermistor is a type of resistor used to measure temperature changes, relying on the change in its resistance with changing temperature. If k is negative, the resistance decreases with increasing temperature, and the device is called a negative temperature coefficient (NTC) thermistor.
Why does resistance decrease with temperature in a thermistor?
Types. Depending on materials used, thermistors are classified into two types: With NTC thermistors, resistance decreases as temperature rises; usually due to an increase in conduction electrons bumped up by thermal agitation from valency band.
What is the main function of a thermistor?
Thermistors are thermally sensitive resistors whose prime function is to exhibit a large, predictable and precise change in electrical resistance when subjected to a corresponding change in body temperature.
What is thermistor and its uses?
The word is a combination of thermal and resistor. Thermistors are widely used as inrush current limiters, temperature sensors (negative temperature coefficient or NTC type typically), self-resetting overcurrent protectors, and self-regulating heating elements (positive temperature coefficient or PTC type typically).
What is thermistor in physics?
A thermistor is a type of resistor whose resistance is strongly dependent on temperature, more so than in standard resistors. The word is a combination of thermal and resistor.
What are thermistors used for?
Thermistors are used as temperature sensors. They can be found in every day appliances such as fire alarms, ovens and refrigerators. They are also used in digital thermometers and in many automotive applications to measure temperature.
What is a thermistor a level physics?
A thermistor is a non-ohmic conductor and sensory resistor whose resistance varies with temperature. Most thermistors are negative temperature coefficient (ntc) components. This means that if the temperature increases, the resistance of the thermistor decreases (and vice versa)
What is a thermistor used for?
How does the resistance of thermistors change with temperature?
The thermistors are resistors whose resistance changes with the temperature. While for most of the metals the resistance increases with temperature, the thermistors respond negatively to the temperature and their resistance decreases with the increase in temperature. Since the resistance of thermistors is dependent on…
How are thermistors used in the real world?
Thermistors can be used as temperature sensors. They can be used to control the output of a circuit depending on the temperature – to automatically switch on a heater when it gets cold, or set off an alarm if a room gets hot. Very little current will flow through the thermistor when the circuit is cold.
What do you need to know about thermistor and LDR?
You should be able to recognise the circuit symbols for a thermistor and an LDR (light-dependent resistor), and know how the resistance of these components can be changed. Thermistors are used as temperature sensors, for example, in fire alarms. Their resistance decreases as the temperature increases.
What kind of oxides are in the thermistors?
They are mostly composed of oxides of manganese, nickel and cobalt having the resistivities if about 100 to 450,000 ohm-cm. Since the resistivity of the thermistors is very high the resistance of the circuit in which they are connected for measurement of temperature can be measured easily.