Simple Machines Simple Machines and Work and Work An interactive unit designed to guide the understanding of 7 th grade students Simple Machines are those machines that are made up of only 1 machine !!! Are these devices simple machines???? By Lucas Kraschnewski
Simple Machines and Work. An interactive unit designed to guide the understanding of 7 th grade students. By Lucas Kraschnewski. Simple Machines are those machines that are made up of only 1 machine !!!. Are these devices simple machines????. Directions. - PowerPoint PPT Presentation
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Simple Machines Simple Machines and Workand Work
An interactive unit designed to guide the understanding of 7th grade students
Simple Machines are those machines that are made up of only 1 machine !!!
Are these devices simple machines????
By Lucas Kraschnewski
DirectionsDirectionsThis unit Simple Machines and Work is
divided into 9 chapters:
Each chapter will have a variety of learning opportunities for you to investigate each topic
including:
(These 5 links are not active, 9 links above are active)
ProcessProcess1. Starting with Ch. 1, proceed through each
unit in order until reaching the end of Ch. 9
2. Complete each chapter in the following order:
A. Read and examine the notes page
B. Watch a video on the topic (if available)
C. Apply your understanding by watching / completing the animations and/or simulations
D. Go to the provided links to gain a deeper understanding
E. Complete the short quiz on each topic to assess your knowledge and e-mail results to teacher
F. Print Lab worksheets provided : complete / turn in
3. After finishing Ch. 9, complete the Unit Exam4. Complete the Rube Goldberg project as your
Question #1: If a box weighs 50 Newtons, how much force do you have to apply to the box to lift it or slide it?
Answer: 50 Newtons (That’s how heavy the box is!!)
Now, let’s say you use a pulley machine to lift the box. The box still weighs 50 Newtons, but you notice you don’t have to lift as hard? You only lift with 25 Newtons of force and the box still can be picked up off the floor.
Has the machine made your job easier? Yes
How much easier? 2 times easier or you only work ½ as hard!!
Ch. 3 - Power!!!Why is this considered a power tool?
Because ….. This electric jackhammer will break apart the concrete faster than he could break the concrete apart by hand!
Definition: The rate (how fast or slow) at which work is done
If Josh and Bill both lift 150N of weight over their heads, to a height of 3 m while exercising, but Josh lifts that weight in 2 seconds and it take Bill 4 seconds, who does more work?
Question-Question-
Neither!! They do the same work (F X D or 150 X 3 = 450J) But….
Josh has more power because he does the same work in less time!!
Definition: Sloping surface that connects 2 points
T / F If you want to slide the box up onto the table and not just lift it straight up onto it, using these inclined planes will reduce the amount of work you have to do?Will these ramps make your job easier? YES!
How can this machine make your job easier, but not reduce the amount of work you do????
10 meters
5 meters
Which one will make your job the easiest?
Index
Inclined Planes
Check It Out!!!* The longer the ramp, which is actually the distance from point A to point B in the diagram, the easier the work becomes (less
force).* You can apply less force to move the car up the ramp, but
you move the car a longer distance. The amount of work you do is the same with all 3 ramps. Remember: Work = Force X
Chapter 5 -ScrewsDefinition: An inclined plane wrapped in a spiral
Try this before moving on!!1. Make 2 right triangles of different lengths, but with the same height.
For example-
2. Bold the long edge of each inclined plane.
3. Wrap one of the triangles around the pencil.
4. Repeat step #3 with the second triangle on a second pencil.
Index
ScrewsLook at those 2 “screws” you just created. What do you notice?*You should see that the purple screw has tighter threads!!
Which screw would be easier to turn into a block of wood? Why?The purple screw, because it started as an inclined plane with a longer ramp, and you should have learned that the longer the ramp the easier your job becomes.
Question:
Why do mountain roads wrap around the mountain and not just go straight up and over the mountain?