Resistors and resistors characteristics, Physics

A resistor is a two-terminal electrical or electronic component that resists an electric current by producing a voltage drop between its terminals in the accordance with ohm’s law.

                                                   R = V/I

The electrical resistance is equivalent to the voltage drop across the resistor divided by the current specifically flowing through the resistor. Resistors are integral part of all electronic circuits. There are basically two types of resistors (1) General purpose (2) high stability. General purpose resistors are of carbon composition. They are inexpensive. They are not so stable and their tolerance is 5 to 20% in value. High stability resistors include metal-film, cermets, metal foil, and wire would resistors. Their tolerances are low and range from 0.1 to 5%. While selecting a resistor, the following points are to be considered:

(1)         Value, size and shape, leads

(2)         Stability

(3)         Tolerance

(4)         Temperature coefficient of resistance

(5)         Power rating

(6)         Maximum operating voltage

(7)         Reliability

(8)         Change in resistance value with frequency

(9)         Load life, environmental condition and age.

The SI unit of electrical resistance is the ohm (O). In an ideal resistor, the resistance remains steady regardless of the applied voltage or current flowing with the device or the rate of change of the current. While real restrictors cannot attain this goal; they are designed to present little variation in electrical resistance when subjected to these changes, or to changing temperature and other environmental factors.

CHARACTERISTICS OF RESISTORS: The following characteristics are inherent in all resistors and can be controlled by design considerations and choice of material.

Posted Date: 7/9/2012 4:04:34 AM | Location : United States






Your posts are moderated
Related Questions
what project can i make that includes induction heating

why does rain water boils faster than fresh water

State Gauss' theorem in electrostatics. Using this theorem, derive the expression for the electric field intensity at any point outside a uniformly charged thin spherical shell.

Plastics are (A) Good conductors of heat. (B) Good conductors of electricity. (C) Bad conductors of electricity. (D) High density. Ans: Plastics are Bad

Hexane is throttled from 18.15 bar, 507.6 K to 0.1 bar.  Determine the temperature at the exit and the entropy generation. Steam is cooled under constant pressure from 400 o C,

i need a full assignment on reflection

luxon: A particle which solely travels at c (the speed of light in vacuum). All of the luxons have a rest mass of zero exactly. Though they are massless, luxons carry momentum

A block goes on a wedge which in turns goes on a horizontal table, as given in figure. The wedge angle is Φ. As long as the wedge is in met with table, we have the trivial const

A light ray is reflected off a plane mirror at an angle of 25° from the normal. A light ray from another source is reflected 54° from the normal. What is the dissimilarity i

A 0.17-kg hockey puck leaves the stick on a slap shot travelling 21 m/s. If no other forces act on the puck, friction eventually will bring it to rest 62 m away. a. Based on th