Thermistors, Physics

Assignment Help:

Thermistors

Insulators and semi-conductors behave in a different way when the temperature increases, because their resistivity decreases. That is: the resistance of an insulator and of a semi-conductor decreases with temperature increase, (their resistance-temperature coefficient is negative!). This feature can be used to advantage as the following example shows.

One example of this effect occurs in a thermistor, which is a thermally sensitive resistor whose resistance alters with temperature; a negative temperature coefficient (n.t.c.) thermistor is one whose resistance reduces with increase in temperature. A thermistor is used in the cooling-water temperature-measuring circuit of a car or lorry; it is inserted in the cooling water and connected in series with the battery and temperature gauge. As the water temperature rises, the resistance of the n.t.c. thermistor falls and allows more current to flow through the temperature gauge; this causes the gauge to indicate variations in water temperature.


Related Discussions:- Thermistors

Disadvantages of d.c. transmission of power, Disadvantages of D.C. Transmis...

Disadvantages of D.C. Transmission of power 1. Electric power cannot be produced at high d.c. voltages because of  commutation problem. 2. The d.c. voltage cannot be stepped

Maximum power transfer in dc circuit, Maximum power transfer: Every sou...

Maximum power transfer: Every source of EMF has internal resistance.  If it is required to develop the maximum possible amount of power in an external load, then the load resis

How to calculate n factor of disproportion reaction, How to calculate n fac...

How to calculate n factor of disproportion reaction? Total number of electron change divided by no. of moles of reactant This is conventional method Total electron chan

Define curie law, Curie law define the magnetic susceptibility of paramagne...

Curie law define the magnetic susceptibility of paramagnetic substances is inversely proportional to the absolute heat i.e.  Where C = Curie constant, T = absolute temperat

How a cph does stop or its speed decreases, How a CPH does stop or its spee...

How a CPH does stop or its speed decreases? Answer; it is a principle that Vc is stable thus that; gradV c =0 Thus, never V c increases or decreases.

Write any four characteristics of electromagnetic waves, Write any four cha...

Write any four characteristics of electromagnetic waves. Give two uses each of 1. Radio-waves 2. Micro-waves.

Emf and size, is there relation between emf and size os cell?

is there relation between emf and size os cell?

Nominal resistance, The resistances of commercially-available discrete resi...

The resistances of commercially-available discrete resistors are restricted to particular sets. For example, the available values of resistors with 10% tolerance are selections fro

Determine the range of source wavelength values, A weakly guiding fibre wit...

A weakly guiding fibre with a particular graded core index has cut-off V-values for its 2nd, 3rd and 4th modes of 2.5, 3.9 and 5.2, respectively. The core radius is 4 microns, the

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd