Energy:

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Heat Energy Transfer Reassessment Review
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Directions

• To start click Slide Show and From Beginning
• As you go through the PowerPoint, take DETAILED
  notes on
• Each Energy Form
• Energy Conversions
• Direction of Heat
• Ways Heat Travel

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Nature of Energy

• Energy is all around you!
• You can hear energy as sound.
• You can see energy as light.
• And you can feel it as wind.

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Nature of Energy

• You use energy when you
• hit a softball.
• lift your book bag.
• compress a spring.

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Nature of Energy

• Living organisms need energy for growth and
  movement.

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Nature of Energy

• Energy can be defined as the ability to do work.
• Work only occurs when something is using energy.

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Forms of Energy

• The main forms of energy are
• Heat
• Chemical
• Radiant
• Electrical
• Nuclear
• Mechanical
• Sound

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Sound Energy

• Sound is the movement of energy through
  substances in longitudinal (compression/rarefactio
  n) waves.
• Sound is produced when a force causes an object
  or substance to vibrate the energy is
  transferred through the substance in a wave.
  Typically, the energy in sound is far less than
  other forms of energy.

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Mechanical Energy

• When work is done to an object, it gains energy.
  The energy it gains is known as mechanical energy
  and is associated with the motion of something.

• It is the total of all the stored (or potential)
  energy AND the kinetic (moving) energy.

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Mechanical Energy Example

• When you kick a football, you give mechanical
  energy to the football to make it move.

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Mechanical Energy Example
When you throw a bowling ball, you give it
energy.
When that bowling ball hits the pins, some of the
energy is transferred to the pins (transfer of
momentum).
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Electrical Energy)

• Power lines carry electromagnetic energy into
  your home in the form of electricity. Electrical
  energy is the energy in the movement of electrons
  (those things buzzing around the nucleus of an
  atom).

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Radiant Energy (Light)

• Light is a form of electromagnetic energy that
  travels in rays through space.
• Each color of light represents a different amount
  of radiant energy.
• Electromagnetic Energy is also carried by X-rays,
  and laser light.

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Heat Energy

• The movement of atoms is called heat energy,
  because moving particles produce heat.
• Heat energy can be produced by friction.
• Heat energy causes changes in temperature and
  state of any form of matter (solid liquid
  gas).

WATCH THIS NOW!!!
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Nuclear Energy

• The nucleus of an atom is the source of nuclear
  energy.

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Nuclear Energy - Fission

• When the nucleus splits (fission), nuclear energy
  is released in the form of heat energy and light
  energy.

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Nuclear Energy - Fusion

• Nuclear energy is also released when nuclei
  collide at high speeds and join together
  (fusion).

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Nuclear Energy
The suns energy is produced from a nuclear
fusion reaction in which hydrogen nuclei fuse to
form helium nuclei.
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Nuclear Energy

• Nuclear energy is we use comes from Uranium and
  is the most concentrated form of energy.

This energy is then used to heat water to make
steam to spin a turbine that spins an electric
generator.
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Chemical Energy

• Chemical Energy is required to bond atoms
  together.
• And when bonds are broken, energy is released.
• Remember the energy released in our Reaction In
  A Baggie Lab?

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Chemical Energy

• Fuel and food are forms of stored chemical
  energy. Food reacts with our bodies releasing
  energy and giving us the ability to move and
  function.

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Energy Conversion

• Energy can be changed from one form to another.
  Changes in the form of energy are called energy
  conversions.

All forms of energy can be converted into other
forms.
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Energy conversions

• The suns light energy goes through solar panels
  and can be converted directly into electricity.
• WATCH THIS!!!

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Energy conversions
Green plants convert the suns light energy
(electromagnetic) into starches and sugars
(chemical energy).
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Other energy conversions

• In an electric motor, electromagnetic energy is
  converted to mechanical energy.
• In a battery, chemical energy is converted into
  electromagnetic energy.
• The mechanical energy of a waterfall is converted
  to electrical energy in a generator.

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Energy Conversions

• In an automobile engine
• 1. the chemical energy in fuel is burned to
  convert -
• 2. into heat energy.
• 3. The heat energy is then changed -
• into mechanical energy to move the car. (it also
  turns into sound energy right!?)

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Chemical ? Heat ?Mechanical
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The Law of Conservation of Energy

• Energy can be neither created nor destroyed by
  ordinary means.
• It can only be converted from one form to
  another.
• If energy seems to disappear, then scientists
  look for it leading to many important
  discoveries.

WATCH THIS!!!
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Vocabulary Words

• energy
• mechanical energy
• heat energy
• chemical energy
• radiant energy
• electrical energy
• nuclear energy
• energy conversion
• Law of Conservation of Energy

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Direction of Heat Transfer

• Heat always moves from a warmer place to a cooler
  place.
• Hot objects in a cooler room will cool to room
  temperature as they give off heat energy.
• Cold objects in a warmer room will heat up to
  room temperature as they gain heat energy.

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Direction of Heat Transfer

• Heat always moves from hotter materials to the
  cooler materials.
• Your warm tea will give energy to the ice cubes
  until both the tea and the ice have reached the
  same temperature.

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Heat travels in three ways, but how can we tell
the difference?
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Heat Transfers
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EXAMPLE OF CONDUCTION

• A piece of cheese melts as heat is transferred
  from the meat to the cheese (Contact)

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Examples of Convection

• Have you ever noticed that the air near the
  ceiling is warmer than the air near the floor? Or
  that water in a pool is cooler at the deep end?
• Examples air movement in a home, pot of heating
  water.

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Examples of Radiation

1. Fire
2. Heat Lamps
3. Sun

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• Conduction Convection Radiation Song