energy
DESCRIPTION
Energy. Energy & Work. Closely related Energy: ability to do work Work: transfer of energy Both measured in Joules. Energy Types. Kinetic Energy: Energy in motion Potential Energy: Stored energy (not moving) depends on position or condition of object . Examples of KE. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/1.jpg)
Energy
![Page 2: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/2.jpg)
Energy & Work•Closely related
•Energy: ability to do work
•Work: transfer of energy
• Both measured in Joules
![Page 3: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/3.jpg)
Energy Types1. Kinetic Energy: Energy in
motion
2. Potential Energy: Stored energy (not moving)
• depends on position or condition of object
![Page 4: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/4.jpg)
Examples of KE
![Page 5: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/5.jpg)
Calculating KE
KE = ½ mv2 m = mass v = velocity
• Which increases kinetic energy more: doubling the mass or doubling the velocity?
![Page 6: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/6.jpg)
Examples of PE
FirecrackerBoulder on top of cliff
battery
![Page 7: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/7.jpg)
Elastic Energy(type of potential energy)
• Energy stored in a compressed material– Example: rubber band, spring
![Page 8: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/8.jpg)
Gravitational PE• PE that depends on object’s
height, and weight
G.P.E. = mgh
m = mass g = 9.8 m/s2
h= height.Which will have greater GPE: a rock on a 3 story ledge or a rock on a 20 story ledge?
![Page 9: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/9.jpg)
Forms of Energy•Mechanical Energy: Related to
motion of objects – Ex : moving machine parts
Windmill Engine piston
![Page 10: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/10.jpg)
Mechanical Energy• PE Converts to KE and vice versa
• Mechanical Energy = KE + PE– Total energy
• Skier• Roller Coaster• Dart
![Page 11: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/11.jpg)
Thermal Energy• Related to heat
•Thermal Energy = total KE and PE of all particles in an object– Particles in matter are constantly
moving
![Page 12: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/12.jpg)
Chemical Energy(type of potential energy)
• Energy stored in chemical bonds within a substance
Ex: Gas, food, human body, battery
![Page 13: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/13.jpg)
Electrical Energy• Energy of Electric Charges
![Page 14: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/14.jpg)
Electromagnetic Energy• Energy traveling in the form of
waves
• X-rays Visible light
![Page 15: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/15.jpg)
Nuclear Energy• Energy stored in nucleus of an
atom• Nuclear Power plants convert
nuclear energy to electricity
![Page 16: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/16.jpg)
Energy conversions•Law of conservation of energy:
•Energy cannot be created or destroyed, only converted from one form to another
![Page 17: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/17.jpg)
Impact crater in Arizona formed within past 20 yrsLarge KE of meteor converted to large amount of thermal energy vaporizing everything inClose proximity
![Page 18: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/18.jpg)
Energy conversions•Light bulb : converts electrical into
thermal and electromagnetic energy
•Compressed Spring: converts potential to kinetic
•Burning wood: stored chemical energy converted to thermal and electromagnetic
![Page 19: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/19.jpg)
If friction is ignored total mechanical energy will remain constant
(KE + PE) start = (KE + PE)end
Pendulum would swing forever!!!
Energy Conversion in a Pendulum
![Page 20: Energy](https://reader036.vdocuments.site/reader036/viewer/2022081507/56815d12550346895dcb1554/html5/thumbnails/20.jpg)
Viewing a Pendulum• Pendulum Energy Conversion