Current Electricity

1. ELECTRIC CURRENT: The coordinated rate of stream of charge is know as electric current.

2. OHM'S LAW: At consistent temperature , the potential distinction V over the finishes of a given metallic wire (conduit) in a circuit (electric) is specifically corresponding to the present coursing through it.

V=IR,

where, I=current,

R= resistance.

3. CURRENT DENSITY j=∆I/∆A current thickness is a vector amount .

4. SUPERCONDUCTIVITY: The resistivity of certain metal or composite drops to zero when they are frosty beneath a specific temperature.

5. CONDUCTIVITY: The equal of resistivity is known as the electrical conductivity of the material.

6. Portability: Mobility is characterized as the greatness of float speed per unit electric field.

7. Interior RESISTANCE OF A CELL: The resistance offered to the stream of current by he electrolyte of the cell is known as the inward resistance of the cell.

8. THE ELECTROMOTIVE FORCE ( EMF) OF A CELL: The measure of work done by a phone in moving a unit positive charge through it from lower potential(negative terminal) to higher potential(positive terminal) is called its electromotive power.

9. POTENTIOMETER: An instrument utilized for measuring precisely the emf or potential distinction is called potentiometer.

10. WHEATSTONE BRIDGE : A system with four resistances P, Q, R, and masterminded , with a phone of emf Є between the focuses an and C and a galvanometer G amongst B and D, is called wheatstone span.

11. Gathering OF CELLS : keeping in mind the end goal to determine most extreme current under given condition, cells can be assembled in the accompanying there various ways.

I. Arrangement GROUPING : various celles are said to be associated in arrangement if negative shaft of one is associated with the positive post of the other et cetera.

II. PARALLEL GROUPING : various cells are said to be gathered in parallel if positive shafts of every one of them are associated with one point and the negative posts to another point.

III. Blended GROUPING : various cells are said to be put in blended gathering in the event that some of them are associated in arrangement and some of them in parallel.

12. RESISTOR( WIRE WOUND AND CARBON RESISTOR): Any object of a directing material having a resistance of craved worth is known as a resistor.

Two noteworthy sorts of resistors are:

a) There are made by winding the wires of some composites on a reasonable base the normally utilized compounds are:

I. Maganin (Cu:84%,Mn:12% and Ni:4%)

II. Constantan (Cu:60%, Ni:40%)

III. Nichrome (Ni:60%,Fe:26%,Cr:12% ,Mn:2%)

The organization changes and the rates given are estimated.

b) CARBON RESISTOR: These are made by embellishment carbon with an appropriate restricting operator into a barrel. Wire leads are joined to the whole resistor is encased in an artistic or plastic coat. They are minimized and have ease.