The document discusses several basic electrical components. It describes batteries as having three parts - an anode, cathode, and electrolyte. Chemical reactions in the battery cause a build up of electrons at the anode. Common battery types are also listed. Resistors are described as passive components that increase electrical resistance and reduce current flow. Capacitors are explained as storing electrical charge between two parallel plates separated by an insulating material. Inductors are coils of wire that can do interesting things due to magnetic properties. Transformers are used to increase or decrease alternating current. Fuses and jumpers are also briefly introduced.

1. CHAPTER -5
CLASS VIII
Mrs. Riffat Shaheen
BASIC ELECTRICAL
COMPONENTS

2. BATTERY

3. Batteries have three parts, an anode (+), a cathode (-),
and the electrolyte. The cathode and anode (the
positive and negative sides at either end of a
traditional battery) are hooked up to an electrical
circuit. The chemical reactions in the battery causes a
build up of electrons at the anode.
An electric battery is a device consisting of two or
more electrochemical cells that convert stored
chemical energy into electrical energy.
Each cell has a positive terminal, or cathode, and a
negative terminal, or anode.

4. The Nickel Cadmium (NiCd) battery.
The Nickel-Metal Hydride (NiMH) battery.
The Lead Acid battery.
The Lithium Ion battery.
The Lithium Polymer battery.

5. A resistor is a passive two-terminal electrical
component that increases electrical resistance of a
circuit element. The main function is to reduce the
flow of electricity in a circuit. In electronic
circuits, Resistors are used to reduce current flow,
adjust signal levels, to divide voltages, bias active
elements, and terminate transmission lines, among
other uses.

7. Capacitors
 A basic capacitor has two parallel plates
separated by an insulating material
 A capacitor stores an electrical charge
between the two plates
 The unit of capacitance is Farads (F)
 Capacitance values are normally smaller, such
as µF, nF or pF

8. Capacitors
 Basic capacitor construction
Dielectric
material
Plate 1
Plate 2
The dielectric
material is an
insulator therefore
no current flows
through the
capacitor

9. Capacitors
Storing a charge between
the plates
 Electrons on the left
plate are attracted
toward the positive
terminal of the voltage
source
 This leaves an excess of
positively charged holes
 The electrons are
pushed toward the right
plate
 Excess electrons leave a
negative charge
+ -
+
_
+ _

10. Capacitors
Types of capacitors
 The dielectric material
determines the type of
capacitor
 Common types of
capacitors are:
 Mica
 Ceramic
 Plastic film

11. Capacitors
 Some capacitors are
polarised, they can
only be connected
one way around
 Electrolytic
capacitors are
polarised

12. Capacitors
 Variable capacitors are
used in communication
equipment, radios,
televisions and VCRs
 They can be adjusted by
consumers by tuning
controls
 Trimmers are internal
adjusted capacitors that
a consumer cannot
adjust

13. Capacitors
 These variable
capacitors would be
difficult to squeeze
into your mobile
phone and iPod
 Current technology
uses semi-conductor
variable capacitors
called varactors
(varicaps)

14. Inductor
 An inductor is about as
simple as an electronic
component can get -- it
is simply a coil of wire. It
turns out, however, that
a coil of wire can do
some very interesting
things because of
the magnetic properties
of a coil.

16. TRANSFORMER
This is an
electrical device
used to increase
or decrease the
value of
alternating
current.

17. Other Electrical components

18. FUSE JUMPERS

19. In electronics and electrical engineering, a FUSE is a type of
low resistance resistor that acts as a sacrificial device to
provide over current protection, of either the load or source
circuit. Its essential component is a metal wire or strip that
melts when too much current flows through it, interrupting
the circuit that it connects. Short circuits, overloading,
mismatched loads, or device failure are the prime reasons for
excessive current. Fuses can be used as alternatives to circuit
breakers.

20. Jumpers are small devices that are used to control
the operation of hardware devices directly,
without the use of software. A jumper is a
mechanical switch that is easily modified by
hand.

21. •WHAT IS A UPS?
•WHAT IS ELECTROMAGNETIC
INDUCTION?
•HOW DOES A ROBOT WORK ???