Have you ever wondered how a simple toy like a slingshot monkey actually works? Well this page is for you. Let’s learn about all the ways that energy causes change around us!
Energy in the universe transfers from form to form and object to object for all eternity. As far as current science knowledge can tell, once upon a time, all of the energy on Earth was created. Since that time, no more energy has been created or destroyed.
ENERGY TRANSFERS occur when energy is passed from one location or object to another.
When we kick soccer ball, Kinetic Energy transfers from our moving foot into the ball to make it move.
ENERGY CONVERSIONS happen when one of the 10 Forms of Energy transforms into another form.
For example, a lightbulb converts incoming ELECTRICAL ENERGY from the wall to LIGHT ENERGY waves that travel through the air to your eyes.
Energy rarely transfers from the beginning form into the intended next form 100%. In the the lightbulb example above, if 100 units of Electrical Energy enter the light bulb, 90 units turn to light and 10 units turn into Heat Energy. This heat energy is not the intended energy form in the transfer so it is considered loss. Energy efficiency is high when very little energy is lost and energy efficiency is low with lots of energy is lost.
Old incandescent lightbulbs were very inefficient because they only transferred 10% of electricity to light energy and the other 90% was lost to heat.
LED lightbulbs are more efficient because they transfer 90% of electricity to light and only 10% of the energy is lost to heat.
“Let’s look at a few more examples…”
MRS. mILLS
For example, a stereo converts ELECTRICAL ENERGY from thew wall to SOUND ENERGY waves that travel through the air to your ear.
Energy loss in this system? Speakers are about 1-5% efficient at this conversion with the majority of energy being lost to heat of components inside of the device.
The sun is a ball of Hydrogen atoms that get fused together into Helium. The nuclear potential energy of these atoms gets transferred into light energy and heat energy which is sent outward into the universe and toward Earth.
Energy loss in this system? Interestingly, there is a reasonable about of Sound Energy generated in this transfer, but the sound isn’t useful to us here on Earth so we consider it a loss.
Plants intake the light energy from the sun and use it to rearrange water and carbon dioxide (CO2) molecules into sugar and oxygen molecules. Through this chemical reaction, the light energy from the sun gets stored in the molecules of the plant as chemical potential energy.
How efficient are plants? Sadly about 5% of light energy that hits a plant is actually transferred to chemical potential energy. Plants can only use the green light wavelengths and they loose a lot of heat in their energy transfer.
Can you describe the energy transfers happening in these image?
What’s next?
I’m lost😱
I need a refresher on Energy Forms!
I need practice🤔
I think I get it, but would like some more practice!
Let’s move on👍
I’m completely comfortable with Energy Transfers, let’s apply them!