You will now create an outline for your final assignment.
In this lesson you learned a great deal about energy—how it relates to work, the differences between kinetic and potential energy, the ways in which moving molecules create thermal energy, and the great assistance offered by the simple machines. Now it’s time to take all that information and turn it into a multimedia project, or a final paper, that summarizes what you’ve learned.
As you compose your project, try to think of ways to connect, either graphically or in writing, some of the facts and concepts you’ve learned in this lesson. One idea is to create a comic strip or labeled drawings that illustrate, for example, the ways in which the seven simple machines make work simpler.
If you create a multimedia project that requires a social-media, video, or audio platform that is not directly offered by this lesson, you will need to post it to a file-sharing site (Dropbox, Google Drive, and Microsoft Teams are examples) and then upload the link to the Write It plug-in. Here are some ideas for what you might want to do:
Use Organize It to outline your ideas. You can review your notes in “My Work” as well as any of the following videos and glossary terms.
| Keyboard Shortcut | Action |
|---|---|
| Space | Pause/Play video playback |
| Enter | Pause/Play video playback |
| m | Mute/Unmute video volume |
| Up and Down arrows | Increase and decrease volume by 10% |
| Right and Left arrows | Seek forward or backward by 5 seconds |
| 0-9 | Fast seek to x% of the video. |
| f | Enter or exit fullscreen. (Note: To exit fullscreen in flash press the Esc key. |
| c | Press c to toggle captions on or off |
Mechanical energy is one of the main types of energy. Objects “move” by forces and change positions. And that movement is transferring energy. But mechanical energy can be separated into different types, depending on whether an object is actively moving (Kinetic) or not (Potential).
Kinetic energy is the energy an object has when it is moving or actively changing positions. A rolling ball, a falling block, or a flipping coin. All of these possess kinetic energy while they are moving.
But objects that aren’t moving have mechanical energy too. The energy they have is in their position and potential to move. A ball perched high on a shelf isn’t changing positions. But it has the potential to. Once it does, that potential energy that is stored in its position is converted to kinetic energy. Potential energy can be a lot, or a little depending on the object's position.
All of this is mechanical or “movement” energy. And because we exist in a universe where things have the potential to move, we’d all do well to understand the role mechanical energy plays in well, almost everything.
| Keyboard Shortcut | Action |
|---|---|
| Space | Pause/Play video playback |
| Enter | Pause/Play video playback |
| m | Mute/Unmute video volume |
| Up and Down arrows | Increase and decrease volume by 10% |
| Right and Left arrows | Seek forward or backward by 5 seconds |
| 0-9 | Fast seek to x% of the video. |
| f | Enter or exit fullscreen. (Note: To exit fullscreen in flash press the Esc key. |
| c | Press c to toggle captions on or off |
Energy moves from system to system, place to place, all the time. And as it moves it interacts with all of the different things around it. One of the ways we can understand these interactions is by measuring the “work done” by that energy within a system.
Energy transferred through a force onto an object has the potential to make that object move. When it does, and that object moves a distance, we measure the overall effect of the energy applied as “work done.”
Work done on a system can be positive when the energy moves the object in the same direction as the force is going.
But when force is applied in the opposite direction of the movement, the work done is negative. Energy is taken away from the system.
And work can also be measured as zero if energy is applied to a system, but there isn’t enough or the direction of the forces are such that there is no displacement and therefore no work done.
Work is a measurement of how energy transfers through a given system with all of its different variables. And if we understand, and can even predict, how energy enters a system and what it will do in that system, we can harness it to do as we please.
Because energy is what makes the world go, but work is what makes it go round.
| Keyboard Shortcut | Action |
|---|---|
| Space | Pause/Play video playback |
| Enter | Pause/Play video playback |
| m | Mute/Unmute video volume |
| Up and Down arrows | Increase and decrease volume by 10% |
| Right and Left arrows | Seek forward or backward by 5 seconds |
| 0-9 | Fast seek to x% of the video. |
| f | Enter or exit fullscreen. (Note: To exit fullscreen in flash press the Esc key. |
| c | Press c to toggle captions on or off |
“Work” in the world of physics is when energy is transferred into a system via forces and those forces move something a distance. But there is a way, thanks to the wonders of physics, to make work easier. Enter the simple machine.
A simple machine is a device either found in nature (ie. your elbow as a lever ) or made by humans (ie. teeter totter as lever) that amplifies work done. These machines take a force and multiply the work-- either by amplifying the forces or increasing the distance moved within a system. So smaller forces can move things longer distances.
Levers, inclined planes, pulleys, a screw, a wedge and the wheel and axle; these are all simple machines. And simple machines can be combined to form complex machines. A wheelbarrow is a wheel + a lever. Scissors are a combo of a lever and a wedge. Either way you slice it, simple and complex machines multiply the work done. Which in a work-a-day world like ours, comes in handy.