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Do Now:

Using your notes from yesterday’s activities, work with your table

partner to develop a definition of energy.

What is Energy?

Ms. Gilliland – Fountain 6

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1. Energy is … the ability to make something happen, or cause an object to change position.

Moving from Point A …

… to Point B

2. There are two general kinds of energy, they are:

POTENTIAL KINETIC

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3. Potential energy is…

stored energy…

waiting to be used.

Examples: Start of a race Fireworks

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4. Another name for potential energy is …

the energy of position.

5. Gravitational potential energy is an object’s stored energy that will allow the object to fall in a downward direction.

What pulls the object down?

GRAVITY!

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6. Gravitational potential energy depends on 2 things …

Weight (of object) Height

What’s the difference?

Mass •  A physical

characteristic. •  The amount of

matter (atoms) inside an object.

Weight •  Is a force. •  The measurement

of the pull of gravity on the mass of an object.

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Gravity on Earth = 9.8 Newtons --- KNOW THIS NUMBER! Weight = Gravity X Mass

7. The greater the weight the greater its potential energy.

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The farther an object has to fall the greater its potential energy.

8. Chemical potential energy is the stored energy in chemicals that is released as heat, light or sound.

OR…

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9. Kinetic energy is

Throwing a stone Speed Skating

the energy of motion.

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10. Kinetic energy depends on two factors:

Mass Velocity

11. The faster an object moves

the greater the kinetic energy.

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The more mass a moving object has the greater the kinetic energy.

… the more difficult it is to stop

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Review Kinetic and Potential Energy

Changing Energy Ms. Gilliland – Fountain 6

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The most common change is from potential to kinetic energy.

12. Energy can change from one form to another.

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Examples: Juggling and bouncing balls …

Examples: Roller coasters As the car speeds along its track – it has

because it is moving! KINETIC ENERGY

As the car slows at the top of a hill – it has

because of where it is, POTENTIAL ENERGY because it is above

the ground and has somewhere to go!

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Let’s take a closer look at a roller coaster …

http://www.teachersdomain.org/asset/mck05_int_rollercoaster/

13. When energy changes form, some of the energy is always changed into heat …

most is “wasted”.

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Thermal pollution is when excess, unused heat energy is released into the environment.

Example: water flowing through a power plant.

Indian Point, Peekskill, NY

14. Even though energy can change form …

Law of Conservation of Energy states that …

energy cannot be created or destroyed only changed in form or position.

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EINSTEIN AND CONSERVATION

OF ENERGY

15. Einstein showed that matter and energy are two of the same thing…

•  Matter can be destroyed to create energy (nuclear power plants, sun)

•  Theoretically, energy could also be turned into matter (not able to do this, yet)

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16. EINSTEIN’S THEORY OF MATTER AND ENERGY WAS STATED IN THE FOLLOWING EQUATION …

E = mc2

c = constant speed of light

m= matter/mass E = energy

What this REALLY means: The TOTAL amount of matter and energy in the universe does not change.