Energy and Stored Energy Essay

Submitted By 1009080chen
Words: 982
Pages: 4
Open Document
1

Welcome to SCIE 150:
The Science of Everything

2

Last Class

3

Today: Energy (Chapter 2)
• Contrast the general properties of the different forms of energy.

• Articulate the difference and relation between
Energy, Power and Work.
• Compare the concepts of Temperature with Heat.
• Examine the implications of the laws of
Thermodynamics in our lives.

• Explore possible sources of energy for our society.

4

Energy
• Doing anything requires energy
• Everyday life “energy” = exuberance
• Physics takes it more seriously: the capacity to do work

• What types of energy can you think of offhand?

5

Two major types: potential, kinetic

Stored energy

Energy of something in motion, something happening

6

Laws of Thermodynamics
• 1st: Energy is conserved
• 2nd: Energy always goes from more useful to less useful forms
▫ There’s no such thing as a free lunch
▫ Everything is taxed...

• 3rd: disorder (entropy) increases

7

Energy – a conserved quantity
• Energy is conserved. What does this mean?

• Can’t be created or destroyed
▫ I can’t suddenly blast off into space
▫ I can’t easily stop a speeding car

• But it can be converted from one form to another
▫ I can eat a chocolate bar, and literally get more energy for running
▫ I can shine a light on a solar panel, and get electrical power for a device

8

Transferring Energy

9

Doing work = the transfer of energy
• You have some money (energy), and in order to do something with it, you have to spend it (do work) 10

Doing Work
• Doing work = transferring energy
• Energy = capacity to do work
• Basic work: force applied through a distance
• The unit of energy (and work): the joule (J)
▫
▫
▫
▫

1 J: lifting a litre bottle of water 10cm
1 slice of cherry pie = 2,000,000 J
Bicycling or rowing: 1,000 J per second
Flashlight battery stores 10,000 J

11

Power
• Power = Energy/time
▫ Watts = Joules/s
▫ A rate of energy flow

• Which uses more power? A:
• Which uses more energy? • Which do you think you get B: billed for?

12

Kinetic Energy
• Energy of motion
• What factors determine it?

• Getting rid of it isn’t easy... 13

Radiative Energy

• What type of light carries the most energy?
• A) Radio B) Visible C) Ultraviolet D) Gamma rays

14

Sound Energy

15

What makes this dangerous?

16

Potential Energy

• Elastic, chemical, electrical, gravitational

17

Another Potential Energy
• Fat Man and Little Boy
▫ The bombs dropped over Nagasaki and
Hiroshima

• Do they have potential energy? • What kind?

18

Mass-Energy
Energy = mass x (speed of light)2
E=mc2

• 1-megaton H-bomb converts mass of a quarter of a can of soda into energy
• The Sun turns some of its mass into energy
• The Big Bang turned a whole lot of energy into the mass of the universe

19

Storing Energy
• We live in an electric world
• How do we store electrical energy that we’ve produced? 20

Gravitational Potential Energy and Kinetic Energy

21

I dare you to physics

Hold a bowling ball to your nose
Release it

• Energies involved? Energy loss?

Should you move your face? 22

Back and Forth

23

Energy Loss?
• 2nd: Energy always goes from more useful to less useful forms
▫ There’s no such thing as a free lunch
▫ Everything is taxed...

• Object pushed on a carpet slides to a stop, what happens to its kinetic energy?
A. It disappears
B. It is turned into heat via friction
C. It is unchanged
D. It is stored as potential energy

24

Friction to Heat

• Friction does work, transferring the energy from
“useful” kinetic to “waste” heat

25

Kinetic Energy and Temperature
• Particles (atoms and molecules) of any material/object always moving…
• Temperature is average kinetic energy of particles.

26

Temperature Scales

27

Heat Flows
• Heat always flows from
Show More

Related Documents: Energy and Stored Energy Essay

Energy and Potential Energy Essay

Chemical potential energy: stored energy. 4. Chemical energy: potential energy stored in chemical bonds or compounds 5. Displacement: vector quantity that measure change in distance, direction or position of an object. 6. Distance travelled: scalar quantity that measure how far and object has moved. 7. Efficiency: ratio of how useful work output to the total work input. 8. Elastic potential energy: energy stored in an object that has it shape changed by stretching. 9. Electrical energy: work done by…

Words 456 - Pages 2

Kinetic Energy Essay example

Energy is the ability to do work. Work is the product of force and distance. Energy is used every day and everywhere. The nuclear reactions in the sun releases heat light and other electromagnetic energy. Corn uses that energy to grow. The corn stores chemical metabolic energy. When the chicken eats the corn it stores energy in itself. When we chicken we store energy inside of us. Then we use metabolic energy and turn it into mechanical energy by pedaling a bike up a hill. The pedaling of the bike…

Words 855 - Pages 4

FUEL FOR PHYSICAL ACTIVITY Essay

FUEL FOR PHYSICAL ACTIVITY The food we eat supplies the energy our bodies need for movement FATS CARBS PROTEINS Stored chemical energy Muscles contract Force exerted on bones via tendon MOVEMENT! Energy in food comes in 3 basic forms • Carbohydrates • Fats • Proteins The body uses a mix of all three sources for exercise, but: • CHO – major source for exercise of moderate to high intensity • FATS – major source for rest and low intensity exercise • PROTEIN – only a minor source and last resort…

Words 956 - Pages 4

Enviro: Energy and Kj Essay

BHARATH KARTHA Total amount of chemical energy stored inside candle wax through a heat of combustion Aim- the aim of this experiment was to find out the total chemical energy that was stored within the paraffin wax and how much of this energy is transferred into the water. Results- Mass of candle (g) Temperature of water ( 0C) Initial 12.6 22 Final 11.8 42 Deviation 0.8 20 Discussion- Heat capacity of water = 4.184J per mL per 0C Total energy absorbed by water (J) = 4.184 x volume of…

Words 502 - Pages 3

Compare And Contrast The Energy Content Of Paraffin And Ethanol

Energy comes in many forms such as light, heat, motion, and potential energy. Chemical fuels such as natural gas and gasoline are chemicals that have a lot of potential energy, which is energy that is stored in the bonds of the molecules. Because they have so much energy stored in them, these fuels have the potential to release energy when their bonds are rearranged and made more stable. Such bond rearrangements release energy into the surroundings often causing a temperature increase. By measuring…

Words 386 - Pages 2

Hydration: Creatine Phosphate Energy Essay

sport Energy systems There are three different types of energy systems within the body. Through the use of adenosine triphosphate (ATP) the body is able to maintain a constant supply of energy. APT is formed during a reaction between adenosine diphosphate (ADP) and a molecule of phosphate. ATP consists of a molecule of adenine and three phosphate groups. When the ADP joins with the phosphate molecule energy is stored within the bonds, when the bonds are broken the energy is released. Energy can…

Words 1076 - Pages 5

Essay on Final Exam Review Project

Karan Shridharani Final Exam Review Project Mrs. Parrot Block 2 Unit 1 ­ Matter Basics ● Matter is anything that has mass and takes up space. ● Energy is the ability to do work or the ability to move or elicit change in matter. ● All matter is made up of particles ● Properties are what we use to identify different substances. ● Physical Properties are shown without any change in composition. ● Chemical Properties are any characteristics that gives a sample of matter , the ability…

Words 1474 - Pages 6

Phat Girls: The Ketogenic Diet

in the case of the fattest man alive In the Guinness Book of Records and in the movie "Phat Girls". However, this does not make being fat a good thing. One way fat is stored up in the body is from excess consumption of carbohydrates or sugars in the body. If you don't burn the calories you eat, they convert and become stored energy (fat) for later use. Thus, an individual gains weight from eating too many calories many times in the form of carbohydrates. But in spite of the fact that fat seems…

Words 556 - Pages 3

Essay about Photosynthesis and Chemical Energy

Section 1 - Directly or indirectly, all of the energy in living systems needed for metabolism comes from the sun. - Photosynthesis is the process by which light energy is converted to chemical energy. - Autotrophs are organisms that use energy from sunlight or from chemical bonds in inorganic substances to make organic compounds. - Most Autotrophs, including plants, are photosynthetic…

Words 590 - Pages 3

What Is Photophosphorylation?

chlorophyll in Photosystem II. The electrons attach to a primary electron acceptor in their excited state. A sequence of redox reactions begins where the electrons pass through some membrane-bound proteins that carry out redox reactions. Energy is released, gathered and stored as ADP. It is then reduced to ATP. The electrons eventually reach a molecule in Photosystem I. The P680 molecule replaces the lost electrons by breaking water into hydrogen and oxygen ions and electrons. The process releases oxygen…

Words 615 - Pages 3