The use of a single fixed pulley and attached cord allows for a change in the direction of the force applied to an object. Although a single overhead pulley provides no mechanical advantage it may be helpful, for example, in allowing a lifting force to be better achieved by redirecting the force down towards the ground to raise an object. Later students can analyse more complex examples with the purpose of identifying the combination of elements they use in their design.
Bring in some tools which are clearly designed with the purpose of increasing the force that can be applied to them bottle opener, crowbar, pliers, car jack and initiate a discussion about what each allows us to do more easily. Guide this discussion so students become aware of how each is able to magnify the force applied to it.
Encourage students to contribute more examples from their own experiences using a screwdriver to get the lid off a paint tin is a good example of an experience many students will have had. Use this to introduce the notion of how levers and other simple machines are used more generally in their lives.
Other simple machines can be introduced one by one by bringing in several examples of each and looking for common features. Steering wheels, screwdriver handles and windlasses are all examples of a wheel and axle; axes, log splitters, tacks and nails are all examples of wedges.
The internet has many sites that provide multiple examples of different simple machines. See the links provided at the end of this focus idea. Have students experience trying to screw the same screw into the same piece of wood with screwdrivers with handles of different diameters.
Many hardware stores sell inexpensive sets of screwdrivers that have a range of handle sizes. Consider removing the plastic handle from a screwdriver and encourage students to experience the difficulty of trying to turn a screw with the shaft alone. Sailing boats are full of ingenious examples of pulleys; rowing boat oars provide one of a few examples where the fulcrum is located such that it reduces the applied force and increase the distance over which it acts.
Generally levers are designed to magnify the forces applied to them. One objective is to highlight just how widespread the uses of simple machines are in our everyday life. Different groups of students could research, construct scale models, study their design and report their findings back to the class on these spectacular simple machines.
The following resources contain sections that may be useful when designing learning experiences:. Our website uses a free tool to translate into other languages. This tool is a guide and may not be accurate. For more, see: Information in your language. You may be trying to access this site from a secured browser on the server. Please enable scripts and reload this page. Skip to content. Page Content. Nail clippers are first class levers.
You can make your own first class lever, using a ruler with a pencil to work as the fulcrum. Begin typing your search term above and press enter to search. Press ESC to cancel. Skip to content Home Essay Why is screwdriver a simple machine? Ben Davis April 15, Why is screwdriver a simple machine?
Is screwdriver an example of lever? Is scissors a simple machine? What are some examples of simple machines in your house? What type of simple machine is a broom? Is a Spoon a first class lever? What is an example of a 1st class lever? What is called first class lever? How do you build a first class lever at home? Previous Article How long is a 7th grade essay?
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