Download Energy - Science with Mr. Enns

Energy
Part 1: What is Energy?
What Is Energy?
Energy takes many different forms
and has many different effects.
But what is it, exactly?
Energy is the ability to cause a change.
It could be a change in…
Shape
Speed
Direction
Composition
2 Categories of Energy
There are 2 main categories of energy:
Kinetic Energy
Potential Energy
The energy of motion
Energy that is stored
Found in things
that are moving
Stored by position,
shape or chemistry
9 Types of Energy
The 9 types of energy fit in these 2 categories:
Kinetic Energy
Potential Energy
Mechanical Energy
Gravitational Energy
Sound Energy
Elastic Energy
Electromagnetic Energy
Chemical Energy
Heat Energy
Nuclear Energy
Electrical Energy
What Forms
form(s)of
ofEnergy
energy Review
is found in
- Game
each object?
1
Mechanical Energy
Sound Energy
Electromagnetic Energy
Heat Energy
Electrical Energy
Gravitational Energy
Elastic Energy
Chemical Energy
Nuclear Energy
What 1 formForms
of energy
of does
Energy
each- need
Game
to make
2 it work?
Mechanical Energy
A ceiling fan?
A solar calculator?
Sound Energy
Electromagnetic Energy
Heat Energy
A wind-up toy?
Electrical Energy
A skydiver?
Gravitational Energy
A battery?
Elastic Energy
Chemical Energy
Nuclear Energy
What form(s)
Forms
of energy
of Energy
do these- appliances
Game 3 produce?
Measuring Energy
Energy can be measured.
In metric nations, it is measured in Joules (J)
1 joule is the equal to the energy needed to
lift one apple from the floor to the table top.
One Joule
(1 J)
Measuring Energy
Energy can be measured.
Non-metric nations measure it in calories (cal).
1 calorie is the amount of energy needed
to raise the temperature of water by 1oC.
One calorie
(1 cal)
Energy Transfers
Energy can change forms.
Energy changes form during an energy transfer.
For example, take a match…
Chemical Potential E
Heat Energy
Electromagnetic Energy
Energy Transfers
Energy can change forms.
Energy changes form during an energy transfer.
Another example…
Gravitational Energy
Kinetic Energy
Changing Forms
Energy can change forms, but it is never lost.
The Law of Conservation of Energy summarizes this:
Energy cannot be created or destroyed. It can
only be changed from one form into another.
Let’s take a look at that match again…
Changing Forms
Energy can change forms, but it is never lost.
Energy cannot be created or destroyed. It can
only be changed from one form into another.
Chemical Potential E
e.g. 1050 J
e.g. 1050 J
Heat Energy
Light Energy
Energy Transfers
Energy transfers can be shown with diagrams.
They are called Energy Transfer Diagrams (ETD).
To create an ETD, follow these steps:
List the STARTING energy on the LEFT.
List the FINAL energies on the RIGHT.
Link them using an ARROW.
Energy Transfers
Energy transfers can be shown with diagrams.
They are called Energy Transfer Diagrams (ETD).
Electrical Energy
Electromagnetic Energy
Heat Energy
List the FINAL energies on the RIGHT.
Electrical Energy à E-Mag Energy + Heat Energy
Energy Transfers
Another example:
Heat Energy
Chemical Energy
Electromagnetic Energy
Sound Energy
Chemical E à Heat E + E-Mag E + Sound E
Any Questions?
Energy
Part 2: Energy Resources
Fuels
There are different types of fuels:
Coal, oil and gas are known as Fossil Fuels.
Fossil fuels are made from the
decomposed remains of living things
that died over 250 million years ago.
Fossil Fuels
The 3 fossil fuels are formed in different ways:
COAL
comes
from the
remains of
dead plants
OIL
comes
from the
remains of
dead sea
creatures
GAS
comes
from the
remains of
dead sea
creatures
Fossil Fuels
Fossil fuels are extremely valuable:
They are used as fuel in cars and homes.
They can be used to produce electricity.
They are used to produce useful products:
Plastics
Rubber
Medicines
Fabrics
Detergents
Cosmetics
Advantages
Fossil fuels have many advantages:
They are an efficient source of energy.
They are convenient to transport and use
They are converted into many materials.
Disadvantages
Fossil fuels have disadvantages as well:
They produce pollutants when burned.
They will eventually run out.
This is why fossil fuels are called
non-renewable energy resources.
Producing Electricity
All energy resources use a turbine
and a generator to produce electricity.
A turbine is a
propeller-like
device which is
made to spin.
The turbine spins
magnets inside the
generator, which
makes electricity.
e.g. Coal Power Plant
A
coal
plant
burns
boil
water
into steam.
The
hot steam
iscoal
then
shot
at
theelectricity.
turbine.
The
The
turbine
generator
spins,
spins
which
totoproduces
turns
the
generator.
Producing Electricity
All energy resources use a turbine
and a generator to produce electricity.
Energy resources differ only by the
way they cause the turbine to spin.
Renewable Resources
Renewable resources will not run out.
Renewable resources are continually
replaced by the processes of nature.
They are considered clean energy sources
because they don’t produce pollutants.
Renewable Resources
Solar Energy
Solar panels gather light energy to heat water
in pipes. The water turns to steam, which is
used to spin a turbine and a generator.
Mojave 2 Solar Plant
Renewable Resources
Wind Energy
The force of the wind in windy areas
drives the blades of a wind turbine,
which spins a turbine and a generator
Offshore Wind Farm
Renewable Resources
Hydroelectric Energy
Water stored high above a dam flows is
allowed to flow down huge pipes. The
rushing water spins a turbine and a generator.
Three Gorges Dam
Turbine – Three Gorges
Renewable Resources
Wave Energy
The repetitive up and down movement
of waves can be used to spin a turbine and a
generator placed vertically in the sea.
Conceptual Wave Plant
Renewable Resources
Tidal Energy
During daily tides, water moves back
and forth. The energy of the flowing water
is used to spin turbine and a generator.
Tidal Power Plant
Renewable Resources
Geothermal Energy
In some locations, rocks below the surface are hot.
Water is pumped through the rocks and is heated into
steam. The steam spins a turbine and a generator.
Iceland – Blue Lagoon
Renewable Resources
Biomass Energy
Plants, wood and animal waste can be burned
as a fuel to heat water into steam. The steam is
used to spin a turbine and a generator.
Wood Biomass Plant
Renewable Resources
Renewables have many advantages:
They will not run out.
They do not produce pollution.
Renewable Resources
Renewables have their disadvantages as well:
They are not as efficient as fossil fuels.
They are expensive to develop and run.
Some can be an eyesore to look at.
Any Questions?
Energy
Part 3: Energy in Foods
Introduction
Food contains stored energy.
Food contains chemical potential energy found
in the molecules that the food is made from.
Our body takes these
molecules in and burns
them in a process called
cellular respiration
Energy In Food
The energy in foods is measured in calories.
1 calorie is the amount of heat energy needed
to raise the temperature of water by 1oC.
Energy In Food
The energy in foods is measured in calories.
1 calorie is the amount of heat energy needed
to raise the temperature of water by 1oC.
But, energy values on most
food labels say Calories …
One Calorie represents
1 kilocalorie, or 1000 calories!
Energy In Food
Energy In Food
The energy in foods is measured in calories.
1 calorie is the amount of heat energy needed
to raise the temperature of water by 1oC.
But, the energy values on
most food labels say Calories …
This really says 180 Kilocalories,
or 180,000 calories.
The Big Three
The energy in food comes from 3 major
substances, called macromolecules:
Fats
Carbohydrates
Proteins
Fats
Fats include come in two forms:
solid (fats) and liquid (oils)
Fats are useful for long-term
energy, cushioning & insulation
Fat-rich foods include nuts,
butter, oils, cheese and meats
Carbohydrates
Carbohydrates come in 2 forms:
sugars and starches
Carbohydrates are the body s
main energy source (50%)
Carb-rich foods include bread,
cereals, pasta, fruit & veggies
Proteins
Proteins are the building blocks
of our cells and tissues
Proteins are made out of
smaller bits called amino acids
Fat-rich foods include milk,
eggs, meat, fish and beans
Energy Values
Each type of macromolecule contains a
different amount of energy, per gram.
Carbs
Proteins
Fats
4 cal / g
4 cal / g
9 cal / g
Any Questions?