Classroom Discussion: Understanding Simple Machines
A simple machine is a simple tool that, when used, makes work easier. In science, work is defined as a force acting on an object to move it across a distance. Pushing, pulling and lifting are common forms of work.
Examine the differences between a fixed pulley, which is attached to a stationary object, and a moveable pulley, which moves with the load. What are the advantages and disadvantages of each?
How might pulleys have been used in the medieval period?
Related Classroom Activity: Using the pulley system, design and create a working drawbridge out of materials provided by your teacher.
Examine and determine the differences between three types of levers: the first class lever (seesaw), the second class lever (wheelbarrow) and the third class lever (fishing pole).
Related Classroom Activity: Draw each type of lever and label them according to the fulcrum, the force and the load.Optional: Find other examples of levers and classify them as first, second or third class.
Related Classroom Activity: Identify each based on their individual designs. Then, design your own catapult or trebuchet with the materials provided by your teacher. Following completion, each catapult or trebuchet will be tested to see which one can hurl an object the farthest. Additional information: An excellent video explaining the principles of the catapult can be found at Wonderville.ca.