Construct the K’nex devices (1 or 2). Analyze how they operate. How is the direction of the force changed? How is the size of the force changed? What is the “trade-off” of reducing the size of the force involved in moving an object when using a simple machine?
Examine the 6 or 7(?) classes of simple machine.
lever, inclined plane, wheel and axle, pulley, gears, wedge, screw
Can you think of examples in your home, at school, around the neighborhood, in the market? Are there other simple devices that do not seem to fall into one of the six or seven classes? What are they (some people might argue there are really only two basic machines).
Combinations of simple machines are called compound or (sometimes) complex machines.
Look through this website. Read through the explanations and examples. Follow the links: https://www.teachengineering.org/view_lesson.php?url=collection/cub_/lessons/cub_simple/cub_simple_lesson01.xml
Something about gears: http://www.explainthatstuff.com/gears.html
Look at the links and references on the previous blogpost.
Homework–Make a subfolder for your energy folder in the DSN. Begin collecting your own photographic record of simple machines you can find firsthand. Be sure to label all the files you upload in your folder. Explain how the different examples work. Explain how forces are applied to do work on the target object. How many of these simple machines can you operate? You might consider short videos showing how you operate the machines.
Short assessment on simple machines, forces, work, and energy next class.