Backgrounders
Children on teeter-totter (axel2001, iStockphoto)
Children on teeter-totter (axel2001, iStockphoto)
Physics, Science,
Let's Talk Science
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How does this align with my curriculum?
Grade | Course | Topic |
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BC5Science Grade 5 (June 2016)Big Idea: Machines are devices that transfer force and energy.
MB5Science Grade 5 (2000)Cluster 3: Forces and Simple Machines
NB5Science 5: Living and Technological Systems (October 2019)Simple Machines
NL5Grade 5 Science (2017)Unit 2: Forces and Simple Machines
NS5Science 5 (2019)Physical Science: Forces and Simple Machines
NU6K-6 Science and Technology Curriculum (NWT, 2004)Structures and Mechanisms: Motion
NUKK-6 Science and Technology Curriculum (NWT, 2004)Structures and Mechanisms: Machines Around Us
NU2K-6 Science and Technology Curriculum (NWT, 2004)Structures and Mechanisms: Movement
NU3K-6 Science and Technology Curriculum (NWT, 2004)Structures and Mechanisms: Stability
NU5K-6 Science and Technology Curriculum (NWT, 2004)Structures and Mechanisms: Forces Acting on Structures and Mechanisms
QCElementary Cycle 2Science and Technology, ElementaryMaterial World
YT5Science Grade 5 (British Columbia, June 2016)Big Idea: Machines are devices that transfer force and energy.
SK5Science Grade 5 (2011)Physical Science – Forces and Simple Machines (FM)
ON2Science and Technology, Grades 2 (2022)Strand D. Structures and Mechanisms; Simple Machines and Movement
ON4Science and Technology, Grade 4 (2022)Strand D: Machines and Their Mechanisms
NT6K-6 Science and Technology Curriculum (NWT, 2004)Structures and Mechanisms: Motion
NTKK-6 Science and Technology Curriculum (NWT, 2004)Structures and Mechanisms: Machines Around Us
NT2K-6 Science and Technology Curriculum (NWT, 2004)Structures and Mechanisms: Movement
NT3K-6 Science and Technology Curriculum (NWT, 2004)Structures and Mechanisms: Stability
NT5K-6 Science and Technology Curriculum (NWT, 2004)Structures and Mechanisms: Forces Acting on Structures and Mechanisms
PE5Science Grade 5 (2012)Simple Machines
PE5Integrated Curriculum Grade 5: Science (Draft 2023)DK 1.4: Simple machines enhance our lives in many ways.
AB8Knowledge and Employability Science 8, 9 (revised 2009)Unit D: Mechanical Systems
AB11Knowledge and Employability Science 20-4 (2006)Unit B: Understanding Common Energy Conversion Systems
AB8Science 7-8-9 (2003, updated 2014)Unit D: Mechanical Systems
BC11Physics 11 (June 2018)Big Idea: Energy is found in different forms, is conserved, and has the ability to do work.
NB11Physics 11 (2003)Momentum and Energy
NS11Physics 11 (2021)Momentum and Energy
NU8Knowledge and Employability Science 8 (Alberta, Revised 2009)Unit D: Mechanical Systems
NU8Science 8 (Alberta, 2003, updated 2014)Unit D: Mechanical Systems
NU11Knowledge and Employability Science 20-4 (Alberta, 2006)Unit B: Understanding Common Energy Conversion Systems
PE10Science 421A (2019)Content Knowledge: CK 3.2
PE11Physics 521A (2009)Momentum and Energy
QCSec IIIScience and TechnologyTechnological World
QCSec IVApplied Science and TechnologyThe Technological World
QCSec IVScience and TechnologyThe Technological World
QCSec VPhysicsTransformation of energy
QCSec IScience and TechnologyTechnological world: Forces and motion
QCSec IIIApplied Science and TechnologyTechnological world
NT8Knowledge and Employability Science 8 (Alberta, Revised 2009)Unit D: Mechanical Systems
NT8Science 8 (Alberta, 2003, updated 2014)Unit D: Mechanical Systems
NT11Knowledge and Employability Science 20-4 (Alberta, 2006)Unit B: Understanding Common Energy Conversion Systems
ON8Science and Technology, Grade 8 (2022)Strand D: Systems in Action
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The lever is a type of simple machine. Learn about the different classes of levers and how they provide mechanical advantage.
Simple machinesare mechanical devices that are used to makeworkeasier. Combinations of two or more simple machines working together are calledcompound machines. These machines create systems for different kinds of movement to occur whenforceis applied to aload. Both simple and compound machines make work easier by changing the size or direction of the force. There are six standard types of simple machines. They are the:
- Lever
- Wheel and axle
- Pulley
- Inclined plane
- Wedge
- Screw
Let us consider the first of these simple machines: the lever.
Misconception Alert
When you hear the word “machine” do you automatically think of something with a motor, like a forklift or a washing machine? Machines do not have to have motors. In fact, a machine is any device that transmits or modifies force.
What is a Lever?
A lever is a simple machine made of a rigidbeamand afulcrum. Theeffort(input force) andload(output force) are applied to either end of the beam. The fulcrum is the point on which the beampivots. When an effort is applied to one end of the lever, a load is applied at the other end of the lever. This will move a mass upward. Levers rely ontorquefor their operation.Torqueis the amount of force required to cause an object to rotate around itsaxis(or pivot point).
What is mechanical advantage?
A lever provides mechanical advantage.Mechanical advantagerefers to how much a simple machine multiplies an applied force. The location of the effort, load, and fulcrum will determine the type of lever and the amount of mechanical advantage the machine has. The farther the effort is away from the fulcrum, the easier it is to move the load.
Mechanical advantage can be calculated using this formula:
If the distance from the effort to the fulcrum is greater than the distance from the load to the fulcrum, then the lever has a mechanical advantage. In other words, the ratio of these two distances is greater than one. This means that a long distance from the effort to the fulcrum and a short distance from the load to the fulcrum will allow a small effort to move a large load!
First Class Levers
There are three types, orclassesof levers.
In afirst class lever, the fulcrum is located between the load and the effort.
If the fulcrum is closer to the load, then less effort is needed to move the load a shorter distance. If the fulcrum is closer to the effort, then more effort is needed to move the load a greater distance. A teeter-totter, a car jack, and a crowbar are all examples of first class levers. First class levers are very useful for lifting large loads with little effort.
Second Class Levers
In asecond class lever, the load is located between the effort and the fulcrum.
If the load is closer to the fulcrum than the effort, then less effort will be required to move the load. If the load is closer to the effort than the fulcrum, then more effort will be required to move the load. A wheelbarrow, a bottle opener, and an oar are examples of second class levers.
Third Class Levers
In athird class lever, the effort is located between the load and the fulcrum.
If the fulcrum is closer to the load, then less effort is needed to move the load. If the fulcrum is closer to the effort, then the load will move a greater distance. A pair of tweezers, swinging a baseball bat or using your arm to lift something are examples of third class levers. These levers are useful for making precise movements.
Levers are very useful simple machines used for transferring force. You may not realize it, but you use levers every day!
References
Afework, B., Hanania, J., Stenhouse, K., & Donev, J. (2018, May 18). Lever. Energy Education.
Curley, R. (2017, June 26). Simple machines. Encyclopaedia Britannica.
Jones, A. Z. (2019, July 20). How does a lever work and what can it do? ThoughtCo.
SoftSchools.com (2019). Levers.
Woodford, C. (2019, August 5). Tools and simple machines. Explain That Stuff.
Simple Machines
Mechanical Systems