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ENERGY

Learning Targets1. I can explain that gravitational potential energy changes in a system as the masses or relative position(s) of objects are changed.

2. I can identify and compare gravitational, elastic, chemical, electrical, and magnetic potential energy.

3. I can, given specific materials, plan and implement an experiment to determine the relationship between the height/mass of a metal sphere and the amount of change it can make to sand held in a container below.

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Vocabulary within this set of notes1. Mechanical Energy: 2. Kinetic Energy: 3. Potential Energy: 4. Gravitational Potential Energy: 5. Elastic Potential Energy: 6. Magnetic Potential Energy: 7. Electrical Potential Energy: 8. Chemical Potential Energy: 9. Electromagnetic /Radiant / Light Energy: 10.Thermal Energy: 11.Sound Energy: 12.Law of Conservation of Energy: 

TYPES OF ENERGY

Energy is the ability to do work or cause change!

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What is Mechanical Energy?

o The amount of work an object can do because of its

motion (kinetic) and position (potential

energies).

When the ball strikes the pins, mechanical

energy is transferred to the pins!

Mechanical Energy= Potential + Kinetic Energy• Gravitational

Potential Energy= The energy an object has that is lifted above a surface

• Kinetic Energy = The energy of movement

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What is Elastic Potential Energy?• Energy that comes from

changing an object’s shape or volume

• Elastic potential energy is stored in the material as work is performed to change its shape or volume.

• Energy is released when the object returns to its original shape

• More deformation = greater potential energy

Magnetic Potential Energy• Magnetic Potential Energy- The force of

attraction or repulsion that results from a magnetic field

• Depends on: • Strength of the magnet

• Distance between objects

Properties: -An object influenced by the field (magnetic) will

either be repelled or attracted to the magnet if it is placed in the field. It has the potential to move!

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What is Electrical Potential Energy?o Energy of an electric charge (caused by the

movement of electrons)

oCaused by electrons attracted to a positive

charge

oEasily transported through power lines and converted into other forms of energy

What is Chemical Potential Energy?o Energy that is

available for release from chemical

reactions.

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What is ElectromagneticEnergy?

o Energy that moves through space as waves

o Includes energy from gamma rays, x-rays, ultraviolet rays,

visible light, infrared rays, microwaves, and radio waves

Radiant (light) Energy: Energy in waves

Also called…

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What is Thermal Energy?o Heat energy

o The heat energy of an object determines how active

its atoms are. A hot object is one whose atoms and

molecules are excited and show rapid movement.

A cooler object's molecules and atoms will show less movement.

Sound Energy• Sound energy is

the energy produced by sound vibrations as they travel through matter.

• Sound vibrations cause waves of pressure.

• Sound energy is a form of mechanical energy at a very small scale!

Vocal Chords

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ENERGY TRANSFORMATIONS• Law of Conservation of Energy –

Energy cannot be created or destroyed, only transformed.

• Energy transformation is the process of changing energy from one form to another.

• Heat (thermal energy) is typically given off as a product of energy transformation. (Think friction!)

Kinetic Energy!

Gravitational Potential Energy