Energy
This presentation is the property of its rightful owner.
Sponsored Links
1 / 25

Energy PowerPoint PPT Presentation


  • 147 Views
  • Uploaded on
  • Presentation posted in: General

Energy. What is Energy?. Energy is the ability to cause change Any time you move, or move something you are using energy. Forms of Energy. What are some forms of energy? Electrical – energy in the form of moving electrons Chemical – energy from a chemical reaction Thermal – energy of heat

Download Presentation

Energy

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Energy

Energy


What is energy

What is Energy?

  • Energy is the ability to cause change

  • Any time you move, or move something you are using energy


Forms of energy

Forms of Energy

  • What are some forms of energy?

  • Electrical – energy in the form of moving electrons

  • Chemical – energy from a chemical reaction

  • Thermal – energy of heat

  • Radiant – the energy of electromagnetic waves including light, gamma rays, microwaves


Converting energy

Converting Energy

  • Energy can be converted between it’s different forms

  • Radiant Energy is converted to chemical energy through photosynthesis


Energy

  • Chemical energy is turned into thermal energy in a fire.


Energy

  • Thermal energy is turned into electrical in a power plant.


Energy

  • Electrical energy is turned into radiant energy in a lightbulb.


Kinetic energy

Kinetic Energy

  • Kinetic energy is the energy of movement

  • KE = ½ mv2

  • m is the mass of an object, v is the velocity of an object

  • Standard units – kg m2/s2 or Joules (J)


Example

Example

  • A jogger who’s mass is 60 kg is moving at 3 m/s, what is the jogger’s kinetic energy?

  • m = 60 kg, v = 3 m/s

  • KE = 1/2(60kg)(3 m/s)2 = 270 J


Example1

Example

  • A car moving at a speed of 20 m/s has a KE of 300,000 J. What is the car’s mass?


Example2

Example

  • A sprinter has a mass of 62.5 kg and a KE of 4000 J. What is the sprinter’s velocity?


Potential energy

Potential Energy

  • Potential energy is stored energy

  • 5 Types of Potential Energy

  • Elastic

  • Chemical

  • Electrical

  • Nuclear

  • Gravitational


Elastic

Elastic

  • Elastic Potential Energy is energy stored by something that can stretch or compress


Chemical

Chemical

  • Chemical Potential Energy is the energy stored in the chemical bonds between atoms.


Electrical

Electrical

  • Electrical Potential Energy is the energy due to the position of an electric charge


Nuclear

Nuclear

  • Nuclear Potential Energy is the energy stored in the nucleus of an atom

  • If you could release all of the nuclear potential energy in you body, you could power the United States for 6 years.


Gravitational

Gravitational

  • Gravitational Potential Energy is energy stored due to an object’s position above the Earth’s surface


Formula for gravitational potential energy

Formula for Gravitational Potential Energy

  • PE = mgh

  • m is the mass of an object, g is the acceleration due to gravity, h is the height above the Earth

  • Standard units – kg m2/s2 or Joules (J)


Example3

Example

  • A 65 kg rock climber climbs a cliff. What is the climber’s potential energy when she is 35 m above the base of the cliff?

  • m=65 kg, h=35m, g=9.8 m/s2

  • PE = mgh = (65kg)( 9.8 m/s2)(35m) = 22295 J


Example4

Example

  • What is the mass of a hiker 200 m above the ground if her GPE is 117600 J?


Example5

Example

  • Find the height of a baseball with a mass of .15kg and has a GPE of 73.5 J?


Kinetic or potential

Kinetic or Potential

  • a moving skateboard,

  • a rock at the edge of a cliff,

  • an unconnected battery,

  • a baseball being pitched,

  • a gallon of gas,

  • a stretched rubber band,

  • a moving car,

  • a person climbing stairs

  • a pizza


Energy can change forms

Energy can change forms

  • What happens when you turn on a lightbulb?

  • What happens to the lightbulb if you leave it on for a long time?


Conversions

Conversions

  • Mechanical energy is the total amount of kinetic and potential energy in a system.

  • ME = KE + PE


Law of conservation of energy

Law of Conservation of Energy

  • Law of Conservation of Energy – energy can not be created or destroyed, only transformed.


  • Login