RESISTOR ARTICLE

RESISTOR

Hello everybody Today our article is about RESISTOR in this article we will Discuss that how it works and how to read it color coding.

INTRODUCTION :

Resistor is an electrical component that is use to reduces the electric current. The ability to reduce current is known as Resistance and is measure in unit of ohm (symbol Ω ).

Resistors may be fixed or variable, 
both controlling the flow of current differently.

A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. Resistors act to reduce current flow, and, at the same time, act to lower voltage levels within circuits.(source wikipedia)

A resistor is an electrical segment that cutoff points or controls the stream of electrical present in an electronic circuit. Resistors can likewise be utilized to give a particular voltage to a dynamic gadget, for example, a transistor.

SYMBOL :

	Resistor	Resistor reduces the current flow.
	Resistor
	Potentiometer	Adjustable resistor - has 3 terminals.
	Potentiometer
	Variable Resistor / Rheostat	Adjustable resistor - has 2 terminals.
	Variable Resistor / Rheostat
	Trimmer Resistor	Presest resistor
	Thermistor	Thermal resistor - change resistance when temperature changes
	Photoresistor / Light dependent resistor (LDR)	Changes resistance according to light

some old and new symbol of resistor 

The symbol used in schematic and electrical drawings for a Resistor can either be a “zig-zag” type line or a rectangular box.

RESISTOR MADE UP OF:

The resistor is made up of following methods:

CARBON RESISTOR: 

•  It is made up of carban or graphite paste.

• 
  

• FILM AND CERMET RESISTOR: 

It made up of conductive metal oxide paste.

• WIRE WOUND RESISTOR :

• Another type of resistor, called a Wirewound Resistor, is made by winding a thin metal alloy wire (Nichrome) or similar wire onto an insulating ceramic former in the form of a spiral helix similar to the film resistor above.

OHM LAW:

The current through in resistor is inversely proportional to its resistance and directly proportional to the voltage across it. Well it is known as OHM LAW.
OR
The resistor current C is equal to the voltage  V accross it and divided by its resistance R

mathematically it is written as:

The resistor's power consumption P   is equal to the resistor's current

times the resistor's voltage V :

P = I × V

The resistor's power consumption P  is equal to the square value of the resistor's current

times the resistor's resistance R :

P = I ² × R

The resistor's power consumption P  is equal to the square value of the resistor's voltage V 

divided by the resistor's resistance R :

P = V ² / R

Rtotal  (EQUIVALENT RESISTANCE) MEASURE :

Resistors in parallel

The total equivalent resistance of resistors in parallel R_Total is given by:

So when you add resistors in parallel, the total resistance is decreased.

Resistors in series

The total equivalent resistance of resistors in series R_total is the sum of the resistance values:

R_total = R₁+ R₂+ R₃+...

So when you add resistors in series, the total resistance is increased.

RESISTOR COLOR CODE:

The resistance of resistor and its tolerance are marked on resistor with color code band which is donoted by its value.

There are 3 types of color codes:

• 4 bands: digit, digit , multiplier, tolerance.
• 5 bands: digit, digit, digit , multiplier, tolerance.
• 6 bands: digit, digit, digit , multiplier, tolerance, temperature coefficient.

		1st Digit		2nd Digit		3rd Digit		Multiplier		Tolerance		Temperature Coefficient
4bands		1		2				3		4
5bands		1		2		3		4		5
6bands		1		2		3		4		5		6
Black		0		0		0		×100
Brown		1		1		1		×101		±1%		100 ppm/ºK
Red		2		2		2		×102		±2%		50 ppm/ºK
Orange		3		3		3		×103				15 ppm/ºK
Yellow		4		4		4		×104				25 ppm/ºK
Green		5		5		5		×105		±0.5%
Blue		6		6		6		×106		±0.25%		10 ppm/ºK
Violet		7		7		7		×107		±0.1%		5 ppm/ºK
Grey		8		8		8		×108		±0.05%
White		9		9		9		×109
Silver								×10-2		±10%
Gold								×10-1		±5%
None										±20%

Resistance calculation of 4 bands resistor

R = (10×digit₁+digit₂)×multiplier

Resistance calculation of 5 or 6 bands resistor

R = (100×digit₁+10×digit₂+digit₃)×multiplier

TYPES OF RESISTOR :

Variable resistor	Variable resistor has an adjustable resistance (2 terminals)
Potentiometer	Potentiometer has an adjustable resistance (3 terminals)
Photo-resistor	Reduces resistance when exposed to light
Power resistor	Power resistor is used for high power circuits and has large dimensions.
Surface mount (SMT/SMD) resistor	SMT/SMD resistors have small dimensions. The resistors are surface mounted on the printed circuit board (PCB), this method is fast and requires small board area.
Resistor network	Resistor network is a chip that contains several resistors with similar or different values.

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Make LFR (Line Following Robot) with Out Microcontroller

Make LFR (Line Following Robot) with Out Microcontroller

Hey Hi everyone today i am going to reveal to you that how to make Line Taking after Robot without utilizing Microcontroller so let,s startAfter Perusing This article you would have the capacity to make your own LFR yet it,s simply needn't bother with Hardware Essential aptitudes additionally require some Fundamental Mechanical abilities too don't Be anxious it,s alright so The primary parts of the Circuit is given beneath 

Sensor part ( Eyes of The LFR ) : 

The firs and Real piece of the LFR venture is the sensor eventually we called it the eyes of the LFR on the grounds that it demonstrates the right way to the LFR the sensor part contain LDR which remains for Light ward Resistor and the second one is Driven Put your sensors in great position a bit above starting from the earliest stage tad bit dubious however not unthinkable .

How it functions ? 

We are utilizing Two LED and Two Ldr for two Dc engines in this undertaking when Driven lights not getting reflection starting from the earliest stage by LDR it,s mean the robot is on Dark line so Engine off on the grounds that the LFR is not on the Right way my mean robot is not going on White shading Track so at whatever point LDR accepting reflection from Drove it`s imply that LFR is going on the Right way WHITE COLOUR  REFLECTION so the DC motor will turn On by 555 .

LDR Sense Light === Turn off the DC Motor
LDR not sence the Light === Turn ON DC motor

Part List or Needs For LFR project

Need 4 resistors of 1k ohm

 Need only One 4.7K and 180R resistor

Need Two Potentiometers a value of 10k 

Need Three Capacitors of 10uF 

Need Two LDRs

Need Two White LEDs 

Need one Diode N4148 

Need Two Transistors BD3904 

Need three  555 Timers ICs

Need Two DC Geared Motors 

Need a 9v or 12V Battery

WORKING ! CHECKED 

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prime number dedector

 Design a digital circuit that turns on LED when 1, 2, 3, 5, 7, 11, 13 causes on a 4 bit data bus.

              

Here we are going to design a digital circuit that glows an LED when prime numbers till 16 is “ON” on a 4 bit data bus. To design such circuit, the apparatus required are:

APPARATUS:

1.  IC 7408, 7432, 7402.

2.  4 10K Ohm resistor.

3.  9 volt battery.

4.  4 dip switches for input.

5.  1 LED.

STEP 1:

To design a digital circuit, the first thing to do is to make a Truth Table. Following Truth Table will be made in order to achieve our task.

D	C	B	A	Y
0	0	0	0	1
0	0	0	1	1
0	0	1	0	1
0	0	1	1	0
0	1	0	0	1
0	1	0	1	0
0	1	1	0	1
0	1	1	1	0
1	0	0	0	0
1	0	0	1	0
1	0	1	0	1
1	0	1	1	0
1	1	0	0	1
1	1	0	1	0
1	1	1	0	0
1	1	1	1	0

The equation obtained from the above Truth Table is following:

Y= D’.C’.B’.A’+D’.C’.B’.A+D’.C’.B.A’+D’.C.B’.A’+D’.C.B.A’+

D.C’.B.A’+D.C.B’.A’

Now from the above equation we will make a Karnaugh Map.

STEP 2:

The second step is to make a Karnaugh Map so that we can simplify our complicated Boolean Expression. Following Karnaugh Map will take place.

	C’D’	C’D	CD	CD’
A’B’
A’B	1
AB	1	1		1
AB’	1		1	1

From Karnaugh Map, we get the following simplified form of equation:

Y= A.D’+A.B’.C+A.B.C’+B.C’.D’

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