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