Inductors

Inductors are a part of electrical circuit. Whichever circuit you take into consideration, there is always a reactive component in the supply circuit. This is due to inductive or capacitive load. Now, What is inductor?

Inductor is a passive component in the circuit that stores energy in the magnetic field created by the current passing through it. So, it is a storing device. The inductor's ability to store magnetic energy is called inductance and it is measured in Henry(H). Inductor is a type of coil wound with conducting material. The more the number of turns the more is its inductance.

Here I give you videos for more explanation.










An inductor is usually constructed as a coil of conducting material, typically copper wire, wrapped around a core either of air or of ferromagnetic or ferri-magnetic material. Core materials with a higher permeability than air increase the magnetic field and confine it closely to the inductor, thereby increasing the inductance.

In Series They add up, i.e.

In Parallel,

Inductors do not allow sudden change in current. If we try to break current suddenly, very heavy voltage builds up due to high rate of change of current and thus voltage shock may occur to operating personnel.
So, safety precautions must be followed.
The voltage that builds up due to break in current is given by,

Inductors are used as chokes to dissipate AC component of supply in rectified DC supply. They are used as voltage regulating component in power circuit as well in developed countries where voltage goes higher than the mentioned limits.

Resistors in a circuit

Resistor is a two-terminal electronic component that produces a voltage across its terminals that is proportional to the electric current through it in accordance with Ohm's law:

V = IR

Resistors are elements of electrical networks and electronic circuits and are ubiquitous in most electronic equipment. Practical resistors can be made of various compounds and films, as well as resistance wire (wire made of a high-resistivity alloy, such as nickel/chrome). They can be made of different kinds of materials. They may be carbon film or even metal strip like tungsten.
When connected in series, their value add up and the resulting value is given by,

Req = R1 + R2 + ..... + Rn

When in parallel they are not additive, instead their resultant value goes down, but powers are additive in that as well. So, In high current application this connection is useful, whereas in high voltage application series connection is required.

In parallel, resultant resistance is given by,



They can be

Carbon composition type
Carbon film type
Metal Film
Wire Wound resistors like rheostats

There are also adjustable resistors like rheostats, potentiometers, strain gauges.

Resistance is measured by color code in electronics.
This color code is as follows.

Color	1st band	2nd band	3rd band (multiplier)	4th band (tolerance)	Temp. Coefficient
Black	0	0	×100
Brown	1	1	×101	±1% (F)	100 ppm
Red	2	2	×102	±2% (G)	50 ppm
Orange	3	3	×103		15 ppm
Yellow	4	4	×104		25 ppm
Green	5	5	×105	±0.5% (D)
Blue	6	6	×106	±0.25% (C)
Violet	7	7	×107	±0.1% (B)
Gray	8	8	×108	±0.05% (A)
White	9	9	×109
Gold			×10-1	±5% (J)
Silver			×10-2	±10% (K)
None				±20% (M)

For example orange, orange and yellow makes 330 kilo-ohms.
334 = 33 × 10,000 ohms = 330 kilo-ohms

Every resistance has power capacity which should not be exceeded in any condition otherwise the resistance may fail.