Chapter 6 – Sources of Energy

CHAPTER 6 – SOURCES OF ENERGY

6.1 Various forms and sources of energyListing various forms and sources of energy on EarthIdentify energy changesExplaining the main source of energy

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WHAT IS ENERGY

Energy is defined as the ability to do work

ELECTRICAL ENERGY Energy carried by an electric current Large amount: Generator and power

plant Other sources ?

LIGHT ENERGY Energy which enables us to see Main source: Sun Other sources ?

HEAT ENERGY Flows from a region with higher

temperature to a region with a lower temperature

Main source: Sun Other sources ?

POTENTIAL ENERGY Energy stored in a body due to its

condition or position

Energy stored in a body due to its condition

Energy stored in a body due to its position

KINETIC ENERGY Energy possessed by a moving object Effected by mass and speed

K.E=1/2 MV2

MECHANICAL ENERGY Total Kinetic and Potential Energy

possessed by an object Produced by: Machines, objects

changing their positions

Moving pendulum

CHEMICAL ENERGY Energy stored in a substance Energy released due to chemical

reactions Sources : Fuels, foods, batteries, green

plant

SOUND ENERGY The energy produced by vibrating

object

Sound energy is important because it enables us tocommunicate and have entertainment.Sound is also used to alert people of something

Sound energy can bedetected by our ears.

NUCLEAR ENERGY Released from fission or fusion

reactions which occur in atomic nuclei Eg: Hydrogen and Uranium Nuclear Fusion: ? Nuclear Fission: ?

FOSSIL FUELS Fossils - remains of microscopic

animal/plant that have decomposed Burning of fossils fuels produces heat

and light Coal, petroleum, and natural gas ? Usage ? Advantage of natural gas ? Disadvantages of coal?

RADIOACTIVE SUBSTANCES Uranium and Plutonium Usage of nuclear energy ?

Nuclear power plant

GEOTHERMAL ENERGY Process of transferring heat from

underground steam to heat up water and produce electricity

Electricity ?

Geyser

Volcano

GEOTHERMAL ELECTRICITY

BIOMASS FUELS Energy obtained from the burning of

organic material Make gaseous and liquid fuels

WATER Kinetic energy of water can be used to

generate hydroelectric energy Energy conversion involve? Disadvantages of hydroelectricity?

WINDo Moving air due to uneven heat around

the Eartho Eg: Windmills and wind turbineso Energy conversion involved?

WAVESo On surface of sea watero Consists of ?o How energy conversion occur?

TIDESo Due to gravitational pull of Moon and

Sun on sea watero Similar like hydroelectricity

THE SUN AS THE PRIMARY SOURCE OF ENERGY

Chemical energy in plants

Heat energy

Solar energy

Atoms - Nuclear - Geothermal

- Wind -Wave -hydroelectricity

- Food - Fossil fuels

CHAPTER 6 – SOURCES OF ENERGY

6.2 Renewable and Non-renewable Energy Define renewable and non-renewable sources of energyGroup the various sources of energy into

renewable and non-renewable energyExplain why we need to conserve energySuggest ways to use energy efficiently

Prepared by Allen

Renewable Energy o Energy that can be replaced when they have

been used.

MEANS : the supply of these energy sources will not be used up

Eg: ?

Non-renewable Energy o Energy that cannot be replaced and will finally

be used up.

o Eg: ?

SOLAR ENERGYo Energy that obtained directly from the Suno Renewableo Usage?o Solar cell and solar panel

THE NEED TO CONSERVE ENERGYo Benefits of energy in daily activities ?o Increase of world’s population and

machines leads to increase in energy consumed

o Most of energy used on Earth come from fossil fuels (Non-renewable Energy)

o Estimated times before depletions

Coal 300-1500 years

Natural gas 50-120 years

Petroleum 40- 70 years

EFFICIENT USE OF ENERGYo Conversion of energy usually not perfect; wasted

as heat energyo Eg:

Bulb (5% useful light energy, 95% heat energy) Car (25% useful and 75% waste)

o Due to fossil fuels are non-renewable, hence maximum energy efficiency was needed

o Way to achieve: Fuel efficiency: Modified engine Cogeneration plants Super-insulated buildings Reduce, Reuse, and Recycle

IMPORTANCE OF CONSERVING ENERGY Use and management of energy sources

1. Transport2. Development3. Agriculture4. Industry