Energy

What is it and where it came from?

A never ending cycle…

Is one of the fundamental parts of the universe

Ability to do work Has different forms

Some forms of energy…

And some more examples…

Common household appliances…

Identify the following household appliances.

R _ F_ _ G _ R _ _ _ R

_ _ E N _ _ A S _ _ R

E _ _ C _ _ I _ _ _ N

Review the Forms of Energy

Determine the form of energy identified by the following images.

Solar

Solar energy in…

Solar water heaters

Solar energy in…

Solar energy can be transformed into electricity.

Solar energy in…

Solar energy for solar cells or photovoltaic energy.

Light

A prism can be used to separate the different wavelengths (represented by the colors) of visible light.

The Light Spectrum

Uses of Light Energy

Chemical and Heat

Chemical Energy in Batteries

Alessandro Volta called his battery the Voltaic Pile. He stacked alternating layers of zinc, cardboard soaked in salt water and silver.

Kinds of batteries

Alkaline battery – Used in Duracell® and Energizer® and other alkaline batteries. The electrodes are zinc and manganese-oxide. The electrolyte is an alkaline paste.

Lead-acid battery – These are used in automobiles. The electrodes are made of lead and lead-oxide with a strong acid as the electrolyte.

Lithium battery – These batteries are used in cameras for the flash bulb. They are made with lithium, lithium-iodide and lead-iodide. They can supply surges of electricity for the flash.

Lithium-ion battery – These batteries are found in laptop computers, cell phones and other high-use portable equipment.

Nickel-cadmium or NiCad battery – The electrodes are nickel-hydroxide and cadmium. The electrolyte is potassium-hydroxide.

Zinc-carbon battery or standard carbon battery – Zinc and carbon are used in all regular or standard AA, C and D dry-cell batteries. The electrodes are made of zinc and carbon, with a paste of acidic materials between them serving as the electrolyte.

Uses of Heat Energy

Sound

Mobile phones could be charged by the power of speech

Mobile phones could soon be charged by simply speaking into the handset.http://www.telegraph.co.uk/technology/news/8500161/Mobile-phones-could-be-charged-by-the-power-of-speech.html

For mobile phone users, a flat battery or a lost charger are among the frustrations of modern life. Now new research promises a way to recharge phones using nothing but the power of the human voice.

Electrical engineers have developed a new technique for turning sound into electricity, allowing a mobile to be powered up while its user holds a conversation. The technology would also be able to harness background noise and even music to charge a phone while it is not in use.

However, there could be a downside to the innovation, if it gives people a new reason to shout into their phones as they attempt to squeeze in every extra bit of power they can.

Dr Sang-Woo Kim, who has been developing the design at the institute of nanotechnology at Sungkyunkwan University in Seoul, South Korea, said: "A number of approaches for scavenging energy from environments have been intensively explored.

"The sound that always exists in our everyday life and environments has been overlooked as a source. This motivated us to realize power generation by turning sound energy from speech, music or noise into electrical power.

"Sound power can be used for various novel applications including cellular phones that can be charged during conversations and sound-insulating walls near highways that generate electricity from the sound of passing vehicles.

"The latter development would have the additional benefit of reducing noise levels near highways by absorbing the sound energy of vehicles."

The technology uses tiny strands of zinc oxide sandwiched between two electrodes. A sound absorbing pad on top vibrates when sound waves hit it, causing the tiny zinc oxide wires to compress and release. This movement generates an electrical current that can then be used to charge a battery.

A prototype of the technology was able to convert sound of around 100 decibels - the equivalent of noisy traffic - to generate 50 millivolts of electricity.

"This is not enough to charge a phone properly, but Dr Kim and his colleagues hope that by altering the material the wires are made from they will be able to produce more energy at lower sounds levels.

He said: "Our current output performance can be applied to various electronic devices with low-power consumption such as self-powered sensors and body-implantable tiny devices. We believe that we can realize more efficient sound-driven nanogenerators."

Researchers and some manufacturers have already started looking at using 'energy scavenging' as a way of powering portable electronic devices.

Scientists have developed devices that can use the heartbeat to power MP3 players, while Nokia has filed a patent for a device which harvests energy from movement, much like a kinetic energy powered watch.

Wind and Mechanical

Uses of Wind Energy

Setting SailWind energy was first harnessed on the Nile to power sail boats down the

river. Since then, boats and ships have been modifying the design of sails to make even better use of the thrust provided by the wind.

Milling AboutWindmills were one of the second most widespread uses of wind energy.

The variety of uses that windmills were put to included grinding grain, as well as pumping water, up until the industrial revolution where the windmill was mostly replaced by the steam engine.

Read more: Uses of Wind Energy | eHow.com http://www.ehow.com/facts_4911458_uses-wind-energy.html#ixzz1YMsVaUwq

Mechanical Energy in Life

Hydroelectric

Geothermal

Nuclear

Types of Energy

Energy makes everything happen and can be divided into two types:

Stored energy is called potential energy. Moving energy is called kinetic energy.

How to measure energy?

BTU (British Thermal Unit) - amount of heat energy it takes to raise the temperature of one pound of water by one degree Fahrenheit, at sea level

[One thousand Btus roughly equals: One average candy bar or 4/5 of a peanut butter and jelly sandwich]

[It takes about 2,000 Btus to make a pot of coffee.]

How to measure energy?

Joule (J) – named after James Prescott Joule

- amount of energy needed to lift something weighing one pound to

a height of nine inches

[1000 J = 1 Btu]

A piece of buttered toast contains about 315 kilojoules (315,000 joules) of energy. With that energy you could:

Jog for 6 minutes Bicycle for 10 minutes Walk briskly for 15 minutes Sleep for 1-1/2 hours Run a car for 7 seconds at 80 kilometers per hour

(about 50 miles per hour) Light a 60-watt light bulb for 1-1/2 hours Or lift that sack of sugar from the floor to the counter

21,000 times!

Over and over again…

Energy can be transformed into

another sort of energy. But it cannot be created AND it cannot be destroyed. Energy has always

existed in one form or another.

Some real life examples…

Stored energy in a flashlight's batteries becomes light energy when the flashlight is turned on.

Food is stored energy. It is stored as a chemical with potential energy. When your body uses that stored energy to do work, it becomes kinetic energy.

If you overeat, the energy in food is not "burned" but is stored as potential energy in fat cells.

Some real life examples…

When you talk on the phone, your voice is transformed into electrical energy, which passes over wires (or is transmitted through the air). The phone on the other end changes the electrical energy into sound energy through the speaker.

A car uses stored chemical energy in gasoline to move. The engine changes the chemical energy into heat and kinetic energy to power the car.

Some real life examples…

A toaster changes electrical energy into heat and light energy. (If you look into the toaster, you'll see the glowing wires.)

A television changes electrical energy into light and sound energy.

Energy Transformations

Follow the loop…

Energy changes form at each step in the food chain. Take an ear of corn as an example.

Sunlight is taken in by the leaves on the corn stalk and transformed through photosynthesis. The plant takes in sunlight and combines it with carbon dioxide from the air and water and minerals from the ground.

The plant grows tall and creates the ears of corn - its seeds. The energy of the sunlight is stored in the leaves and inside the corn kernels. The corn kernels are full of energy stored as sugars and starch. The corn is harvested and is fed to chickens and other animals. The chickens use the stored energy in the corn on the cob to grow and to move. Some energy is stored in the animal in its muscle tissue (protein) and in the fat.

Follow the loop…

The chicken reaches maturity, a farmer slaughters it and prepares it to be sold. It's transported to the grocery store. Your parents buy the chicken at the supermarket, bring it home and cook it (using energy).

You then eat the chicken's meat and fat and convert that stored energy into energy in your own body. Maybe you ate the chicken at a picnic. Then you went and played baseball. You're using the energy from that chicken to swing the bat, run the bases and throw the ball.

As your body uses the energy from the chicken, you breathe in oxygen and exhale carbon dioxide. That carbon dioxide is then used by other plants to grow.

Reference

http://energyquest.ca.gov/story/index.html