Current,Voltage and Potential difference

By Nirmal -
Current :
The rate of flow of electrons through a circuit is defined as current . In general current is denoted with "I or i".The unit of current is coulombs/sec which is called as "amperes(A)".

Voltage or Potential:
Voltage is measure of the work required to move charge from one point to another in electric field. Its unit is Joules/Coloumb called as Volt (V). V=w/q.

Potential difference :
(i) the difference in electrical potential between two points in a circuit expressed in volts(V).
(ii) the difference in electrical charge between two points in a circuit expressed in volts(V).

Comments

Post a Comment

Popular posts from this blog

The Difference between single phase and three phase system?

By Nirmal -
Phase is the differnce between waves, through which the current flows. 1 phase consists of 3 wires , 1 phase 1 neutral and 1 stay wire. 3 phase consists of 5 wires , 3 phases(R, Y, B), 1 neutral and 1 stay wire. In most of the transformers 3 phases are mostly used except the road side transformers because the voltage of 3 phase is 440v. In domestic appliances 1 phase is used because the voltage required is 230v 1. Single phase voltage is compare then three phase voltage is very low for ex- 1 phase 240v < 3 phase 440v. 2. Three phase can make rotating magnatic field but single phase can not make rotating magnatic field. 3. In three phase is phase sequence but single phase is not phase sequence.
Read more

Indoor Transformer Installations

By Nirmal -
Image
Indoor 1. Only dry type transformer shall be installed inside residential./ commercial buildings. While using oil filled transformers certain steps are there to be followed: a. it must be installed OUTDOOR only. b.Easy access of fire station vehichles. c.the transformer room/building must be 1.5 mtr away from the residence/commercial building d. the substation must be weather proof, walls must have minimum thickness of 230mm of thick RCC, Fire resistant wall must be there. e. outside corporation area minimum distance between transformer and substation must be 6m. 2. dry type transformer must be installed above ground floor. 3.ABSF/VCB ust be provided at primary side. 4. Minimum cable size at primary must be 150sq.mm XLPE (aluminium) or 70 sq.mm XLPE (Aluminium) if backup fuse is provided. 5.Oil filled TRFR must be segregated from HT and MV switchgear. 6.oil drainage facility/soak pits must be provided for oil filled transformers if oil quantity is above 2000 litres.
Read more

Electrical phenomena in nature

By Nirmal -
Image
Electricity is not a human invention, and may be observed in several forms in nature, a prominent manifestation of which is lightning. Many interactions familiar at the macroscopic level, such as touch, friction or chemical bonding, are due to interactions between electric fields on the atomic scale. The Earth's magnetic field is thought to arise from a natural dynamo of circulating currents in the planet's core. Certain crystals, such as quartz, or even sugar, generate a potential difference across their faces when subjected to external pressure. This phenomenon is known as piezoelectricity, from the Greek piezein (πιέζειν), meaning to press, and was discovered in 1880 by Pierre and Jacques Curie. The effect is reciprocal, and when a piezoelectric material is subjected to an electric field, a small change in physical dimensions take place. Some organisms, such as sharks, are able to detect and respond to changes in electric fields, an ability known as electroreception, while o
Read more