Chapter
# 3
Alternating
Current
An
electric current is a flow of electric
charge. In electric
circuits this charge is often carried by moving electrons in a wire. It can also be carried by ions in an electrolyte,
or by both ions and electrons such as in a plasma.
The
SI unit
for measuring an electric current is the ampere, which is the flow of electric
charges through a surface at the rate of one coulomb per second. Electric current can be
measured using an ammeter.
Electric
current causes many effects, notably heating, but also induce magnetic fields,
which are widely used for motors, inductors and generators. By another definition electrical current which changes
its direction and strength. We should know how about AC & DC current. Some people may ask that why in Pakistan, India and some other Asian countries the Frequency is 50 cycle per second and Voltage is 220 Volts (Phase to Neutral) while in European and western countries, frequency is 60 Cycle per second and Voltage is 110 Volts.
You can get the answer of the above question by clicking the link below. In chapter three, you will acquire knowledge about Alternating current. It is very important to read out the whole chapter.
For reading this chapter, what you have to do is just go the link given below and click on the link. When you will click the link the chapter will be opened and you can access the chapter.
For opening of Chapter three please click
Download: Alternating Current - Chapter # 03
