Special resistor materials: carbon, Physics

Carbon:

Atomic number

6

Symbol

C

Atomic weight

12.011

Discovery

Carbon exists free in nature and has been known since prehistoric time.

Electronic configuration

[He] 2S2 2p2

Word origin

Latin name carbo, French name carbon, coal or charcoal.

me n contact Melting point

34500C

Electrical resistivity

400-1200*10-8 ohm-m.

Properties:

1.      Carbon is found free in three forms: Amorphous, Graphite and Diamond.

2.      It has negative temperature coefficient of resistance.

3.      Its resistance is pressure sensitive. As pressure increases electrical resistance of the carbon emcontact decreases.

4.      It can withstand arcing.

5.      It has not a very good abrasive resistance.

6.      Diamond is one of the hardest substances with a high melting point and index of refraction.

Uses:

1. Carbon is used in applications like brushes for electrical machines electrodes for electric arc furnaces non wire resistors battery cell element are lamps are welding etc.

2. Carbon is also used in some telecommunication equipments like potentiometers microphones etc.

3. Diamond is prized as a gemstone and is used for cutting, drilling and as bearing.

4. Graphite is used as crucible for melting metal, in pencils, for rust protection, for lubrication, an as a moderator for showing down neutrons for atomic fission.

5. Amorphous carbon is used for removing tastes and odours.

Posted Date: 7/21/2012 7:50:24 AM | Location : United States







Related Discussions:- Special resistor materials: carbon, Assignment Help, Ask Question on Special resistor materials: carbon, Get Answer, Expert's Help, Special resistor materials: carbon Discussions

Write discussion on Special resistor materials: carbon
Your posts are moderated
Related Questions
type of mirror used

What do you mean by normal adjustment of a telescope? In What way it is better? What is the need of erecting lens in a terrestrial telescope? What do you mean by its magnific

What are the kinds of energy?

De Broglie wavelength (L. de Broglie; 1924) The prediction which particles also have wave characteristics, where the effective wavelength of an element would be inversely propo

A thin rod of length 1 m is fixed in a vertical position inside a train, which is moving horizontally with constant acceleration 4 m/s2. A bead can slide on the rod, and friction c

The process of apparent change in frequency (or wavelength) of the light because of relative motion among the source of light and the observer is known as Doppler's effect.

It is a mathematical explanation of the disturbance prepared by a ray. For a string, the wave function is a distance for sound rays. It is a density or pressure fluctuation while f

screw gauge mostly based on what theory


Q. Illustrate what is moment of inertia? Answer:- Moment of inertia is the term utilized to measure or quantifies the amount of mass located at an object's extremities. Fo