10 sources of energy

Std-8th Sub-Science

Topic-Sources of energy

Std-8th Sub-Science

Topic – 10

Std-8th Sub-Science


10.1 Fossil fuel10.2 Forms of fossil fuel10.3 Sun10.4 Solar cooker & Solar heater10.5 The solar cell10.6 Other sources of energy10.7 Atomic energy

Introduction

Std-8th Sub-Science


ENERGY

The capacity to do work

is called energy.

Although energy has

many forms ,it can be

changed from one form into

another.

Std-8th Sub-Science


A substance that

produced energy on

burning is called fuel.

Std-8th Sub-Science


A lakes of years ago because of

different calamities ,remnants of

plants and animals got buried into

the earth. Due to effect of the

tremendous pressure of layer of the

earth above the heat inside they

were converted into fuel. Such fuels

are called fossil fuel

Std-8th Sub-Science


Fossil fuel formation

Std-8th Sub-Science


Fossil Fuel

Solid

Liquid

Gaseous

Forms of fossil fuel-

Std-8th Sub-Science


1.SOLID FUEL

It was made from remains of plants.

Firewood and brushwoodare used in rural areas.

Charcoal is formed when wood is burnt in insufficient air. Charcoal burns smoke less.

Std-8th Sub-Science


2.LIQUID

Mineral oil is found nearly 25,000 meters deep in the bowels of the earth.

Petrol, diesel, kerosene and fuel oil can be obtained from it .

70 percent mineral oil we use.

Std-8th Sub-Science


3. GASEOUS

•Natural gas is lights up quickly and burns

without leaving behind any solid

substances. Besides, it is easy to transport

form its main source by means of pipes

over long distances. A big advantage is

that the burning of natural gas can be

easily controlled.

•Ex. methane [CH4], ethane[C2H6],

propane[C3H8], butane[C4H10], etc.

Std-8th Sub-Science


Sun

The earth gets a tremendous

amount of energy from the

sun as much as 7 x 1017

kilowatts per year.

Std-8th Sub-Science


Std-8th Sub-Science


Solar cooker and solar heater

In this devices, mirrors are used

to collect and concentrate solar

energy.

It can be used to cook food or

heat water, etc.

Std-8th Sub-Science


Std-8th Sub-Science


Solar cell

In the solar cell, solar energy

is converted into electric

energy and this can be used

at night for lighting.

Std-8th Sub-Science


Fossil fuel

They cannot be produced a

new, therefore, they are called

to be conventional or non-

renewable sources of energy.

There are only limited

deposits of fossil fuel.

Std-8th Sub-Science


Solar energy•It is always available, so

they are called non-

conventional or renewable

source of energy.

Std-8th Sub-Science


Other sources of energy

Wind energy,

hydro- electric energy,

biogas,

bio-diesel

Std-8th Sub-Science


Std-8th Sub-Science


Problem created by using conventional sources of energy

• Global warming – Gases like carbon-dioxide,

carbon-monoxide, hydrogen sulphide causes

problem of population.

• Pollution – Carbon-dioxide and many other

gases causes problem of pollution.

• Depilation of ozone layer- gases like CFC

causes holes in ozone layer of atmosphere.

• Deforestation-Due to cutting trees causes

number of forest become dwindled.

Std-8th Sub-Science

Creation


10 sources of energy

Education