This document discusses resistors and conductors. It defines a resistor as an electrical component that limits current flow, and notes they can be used to provide voltage for devices like transistors. It describes two types of resistors - fixed and variable. Variable resistors include rheostats and potentiometers. The document also discusses conductor materials like copper that allow current to flow through the movement of electrons. Color codes are provided for reading resistor values.

1. Created by:
Hamza
CONDUCTOR AND
RESISTOR

2.  Resistor
 Types of Resistor
 Connection of Resistor
 Color coding table
 Example
 Conductor
 Flow of current
TABLE OF CONTENT

4. A resistor is an electrical component that
limits or regulates the flow of
electrical current in an electronic circuit.
Resistors can also be used to provide a
specific voltage for an active device such as
a transistor.
RESISTOR

5.  The ratio of the voltage applied across a resistor
terminals to the intensity of the current through the
circuit is called resistance
 This relation is represented by OHM’s Law:
V=IR
 The OHM (SYMBOL: Ω) is the SI unit
of the electrical resistance of
electrical resistance.
RESISTOR

6. There are two types of resistor:
TYPES
FIXED RESISTOR
VARIABLE RESISTOR

7. FIXED RESISTOR
• CARBON COMPOSITE
RESISTOR
• FILM RESISTOR
• WIRE WOUND RESISTOR
• RESISTANCE WIRE
VARIABLE RESISTOR
• RHEOSTAT
• POTENTIOMETER
• THERMISTOR
• HUMISTOR
• VARISTOR
• PHOTORESISTOR
TYPES

8. LOW INDUCTANCE
VERY CHEAP TO MAKE
HAVE VERY LARGE TOLERANCES
IDEAL FOR HIGH FREQUENCY APPLICATIONS
CARBON COMPOSITE RESISTOR

9.  THE RESISTIVE VALUE OF THE RESISTOR IS
CONTROLLED BY INCREASING THE DESIRED
THICKNESS OF THE DEPOSITED FILM.
 RESISTANE UPTO 10MΩ CAN BE OBTAINED.
 HAVE TOLERANCE 1% OR LESS
FILM RESISTOR

10.  MADE BY WINDING A THIN METAL
ALLOY WIRE ONTO AN INSULATING
CERAMIC FORMER IN THE FORM OF A
SPIRAL HELIX
 AVAILABLE IN VERY LOW OHMIC AND
HIGH PRECISION VALUES
(FROM 0.01 TO 100KΩ)
WIRE WOUND RESISTOR

11.  RHEOSTAT IS A ADJUSTABLE RESISTOR USED IN
APPLICATIONS THAT REQUIRE ADJUSTMENT OF
CURRENT OR VARYING OF RESISTANCE IN
AN ELECTRIC CIRCUIT
 A SPECIAL TYPE OF RHEOSTAT IS
THE POTENTIOMETER
RHEOSTAT

12.  A POTENTIOMETER IS, A POT, IN ELECTRONICS
TECHNOLOGY IS A THREE-TERMINAL
RESISTOR WITH A SLIDING CONTACT THAT FORMS
AN ADJUSTABLE VOLTAGE DIVIDER.
 POTENTIOMETERS ARE COMMONLY USED TO
CONTROL ELECTRICAL DEVICES
SUCH AS VOLUME CONTROLS,
JOYSTICKS ETC.
POTENTIOMETER

13.  A THERMISTOR IS A TYPE OF RESISTOR
WHOSE RESISTANCE VARIES
SIGNIFICANTLY WITH TEMPERATURE
 THERMISTORS CAN BE USED AS
CURRENT-LIMITING DEVICES FOR
CIRCUIT PROTECTION, AS
REPLACEMENTS FOR FUSES.
THERMISTOR

14.  A HUMISTOR IS A TYPE
OF RESISTOR WHOSE RESISTANCE
VARIES SIGNIFICANTLY WITH HUMIDITY.
 A HUMIDITY SENSOR MEASURES THE
HUMIDITY LEVEL BY MEASURING THE
CHANGE IN THE RESISTANCE OF AN
ELEMENT
HUMISTOR

15. A VARISTOR (OR VOLTAGE DEPENDENT RESISTOR )
FUNCTION IS TO CONDUCT SIGNIFICANTLY INCREASED
CURRENT WHEN VOLTAGE IS EXCESSIVE.
VARISTOR
HIGH VOLTAGE VARISTOR

16.  A PHOTORESISTOR OR LIGHT DEPENDENT
RESISTOR(LDR) EXHIBITS
PHOTOCONDUCTIVITY.
 PHOTORESISTORS IN MANY CONSUMER
ITEMS SUCH AS STREET LIGHTS, CLOCK
RADIOS, ALARM,DEVICES ETC
PHOTORESISTOR

17. SERIES CONNECTION
• IN SERIES CONNECTION, THE CURRENT REMAINS CONSTANT.
(i.e. I = I1 = I2 = …. = In )
• IN SERIES CONNECTION, VOLTAGE ADDS UP.
(i.e. V = V1 + V2 + …. + Vn)

18. PARALLEL CONNECTION
• IN PARALLEL CONNECTION, THE VOLTAGE REMAINS CONSTANT.
(i.e. V = V1 = V2 = …. = Vn)
• IN PARALLEL CONNECTION, CURRENT ADDS UP.
(i.e. I = I1 + I2 + …. + In )

19. COLOR CODE TABLE

20. EXAMPLE

21. A conductor is an object or type of material
that allows the flow of an electrical current in
one or more directions. A metal wire is a
common electrical conductor
like copper or aluminum.
CONDUCTOR

22. One or more electrons from each atom are
loosely bound to the atom, and can move freely
about within the metal. These conduction
electrons are the charge carriers in metal
conductors.
CONDUCTOR

23. HOW CURRENT FLOW

24.  The reciprocal of resistance is called conductance (G)
measures in Siemens (S).
G = 1/R
 Conductance measures how easily electricity flows along
conductor.
CONDUCTANCE