Energy

What are some ways we use or see energy being used?

Some forms and uses of energy

What is energy?

• Energy is the ability to do work or cause change.

• What types of energy do you see in this photo?

•Nuclear energy (sun)•Chemical energy (plants)•Thermal energy (melting snow)•Mechanical energy (moving water)•Light energy (visible light)

Everything we do is connected to energy use.

Energy is usually described as kinetic or potential

Different forms of Energy

• Kinetic Energy- the energy an object has due to its motion.

Kinetic energy increases when you have more mass.

•The green ball has more kinetic energy because it has more mass. •So it makes a bigger splash!

Which ball will make a bigger

splash?

Kinetic energy increases when you have more speed

Will the ball go farther with a slow swing or a fast swing? Why?

A fast swing has more speed, therefore, more kinetic energy and the ball will go farther.

• Potential Energy- the energy an object has stored, often due to its position.

Which skier has more potential energy? Why?

Skier 1 has more potential energy because they are

at a higher position than

skier 2.

http://www.youtube.com/watch?v=vl4g7T5gw1M

Roller Coasters use potential and kinetic energy to create an exciting ride

http://www.youtube.com/watch?v=0H5_jrwSA3w

Try it!

• Create a roller coaster with just the right balance of potential and kinetic energy so it doesn’t crash!

http://www.brainpop.com/games/coastercreator/

Is it Kinetic or Potential?

Classify the following as a type of potential energy or kinetic energy (use the letters K or P)

1.A bicyclist pedaling up a hill

2.An archer with his bow drawn3.A volleyball player spiking a ball 4.A baseball thrown to second base5.The chemical bonds in sugar 6.The wind blowing through your hair7.Walking down the street 8.Sitting in the top of a tree9.A bowling ball rolling down the alley 10.A bowling ball sitting on the rackWhat can you find in your home that are examples of

kinetic and potential energy? Name two for each type of energy.

Kinetic Energy Lab• You will be testing the factors that affect

kinetic energy by recording the distance a marble will roll down a ramp.– You will change its mass and its speed (angle of

the ramp) and describe how this affects its energy.

Kinetic Energy• The faster an object moves, the more kinetic

energy it has.• The greater the mass of a moving object, the

more kinetic energy it has.• Kinetic energy depends on both mass and

velocity.

Potential Energy• “The bigger they are the harder they fall” is not

just a saying. It’s true. Objects with more mass have greater P.E.

• The formula to find P.E. isP.E. = Weight X Height.

• http://vitalnj.pbslearningmedia.org/asset/mck05_int_rollercoaster/

Energy forms and transformations

http://phet.colorado.edu/en/simulation/energy-forms-and-changes

http://www.pbslearningmedia.org/resource/hew06.sci.phys.maf.trebuchet/energy-transfer-in-a-trebuchet/Trebuchet potential into kinetic energy

How does the bulb light up?What forms of energy are seen?

• The bulb gets its energy from the battery.

• There is chemical energy in the battery

• Electrical energy in the wires• Thermal energy in the bulb

filament• Light energy and thermal energy

seen from the bulb.• Energy changes form to light the

bulb.