electricity
Post on 10-Feb-2017
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SCIENCECLASS 6
WHEN THERE IS A POWER CUT?
Electric current:
Flow of charge (electrons) through a conducting wire in a unit time.
SOURCES OF ELECTRIC CURRENT
GENERATOR
BATTERY
What are CONDUCTORS?
What are INSULATORS?
MATERIALS THAT DO NOT ALLOW CURRENT TO PASS-INSULATORS
MATERIALS THAT ALLOW CURRENT TO PASS-CONDUCTORS
HOW IS ELECTRICAL
ENERGYPRODUCED IN A
CELL??
When electrodes are placed in the electrolyte.
the production of electricity is by a chemical reaction that changes chemical energy into electrical energy
Electrical energy is from the chemicals inside them.
Can’t be charged Eg: dry cells and simple voltaic cells.
Electrical energy produced by chemical reaction within.Chemical reactions are reversible, hence energy is stored.Can be charged Eg: lead accumulator and nickel-iron accumulator
PRIMARY CELLS
used in torches, wall clocks, toys, etc
SECONDARY CELLS
used in mobile phones, car batteries, etc.
SOLAR/PHOTOVOLTAIC CELL:
WORKING OF PRIMARY
CELL
Cathode is the positive end.Here the cathode is Carbon
Anode is the negative end.Here the anode is Carbon and Manganese dioxide mixture
HENCE IN THE DRY CELL,CELL THE FLOW OF ELECTRICITY IS FROM CARBON ROD TO THE ZINC END.
FLOW OF ELECTRICITY IS FROM POSITIVE END TO NEGATIVE END
The complete path for flow of electric current from one terminal to the other terminal is known as an electric
circuit.
A CIRCUIT MIGHT BE
CLOSED OR OPEN
COMMONLY USED SYMBOLS
SWITCHES
Electrical Switches control the flow of electric current
open circuit and the current will not flow
closed circuit and the current will flow
PART FUNCTIONbulb Produces light
Reflector&lens
helps to focus light
Plastic body Holds the parts
switch Controls flow of current
battery Source of power
PARTS OF A LIGHT BULB
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