Simply Amazing Machines! - Celebrating International Skeptics Day - Vol.4 #5
January 16, 2018
"Give me a lever long enough and a fulcrum on which to place it, and I shall move the world." - Archimedes
Everyday we are using machines and sometimes do not even realize it. Teaching our students about simple machines is crucial to their understanding about how something works.
Simple machines are designed to help make something easier. The mathematician, scientist and inventor, Archimedes, is credited for enhancing our knowledge of simple machines, though he did not invent them. Evidence has been found that these devices, especially levers, have been being used since 5000 b.c.
Here are 6 of the most common simple machines that helps us day to day. There is also a video at the end of each description that you can share with your students, to better help them understand what these mechanisms do!
Pulley- consists of a rope and wheel and helps us to lift something that is too heavy to lift ourselves. Some examples of a pully include elevators, certain types of weight lifting machines and cranes.
Inclined Plane- is a surface that is tilted at an angle. It helps to move something from a lower surface to a higher one with ease or vice a versa. Slides and ramps are examples of an inclined plane.
Lever- helps us to lift materials using a fulcrum as a pivot point. It can remove materials from tight objects and cut items into pieces. Examples include scissors, pliers
and tongs.
Screw- is used to hold things together by turning rotational motion into linear motion.
Wedge- can be used to seperate something or keep an object in place. An example of a wedge could be an axe, or a doorstop.
Wheel and Axle- is fixed together, so
that they both rotate at the same time. These two components working together can help us reduce friction and also helps us by amplifying force. You are seeing a wheel and axle working together when you ride a bicycle or are looking at gears.
We all use these machines each day to help us accomplish simple tasks. By helping our students understand the functionality of them, they will be able to understand how larger, more involved machines work at their core.
Understanding the Mechanical Advantage of a Pulley
This is a great activity for your middle schoolers, but if you believe your students can benefit from it, go for it! In this activity your students will understand the mechanical advantage of a pulley by working together in teams to build hypotheses and test the outcome. You will need materials such as nylon rope, two-wheeled pulley, a single pulley, a spring scale and weight (soup cans, rocks, weights, etc.) For more information on this activity please visit the EFGI website!
Let's Build a Catapult