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Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
SimpleMachinesWorkshop
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
What is a Simple Machine?
Definition: A simple machine is a device, or tool, which
makes work easier.
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
IdentifyingSimple Machines
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Inclined Plane
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Wedge
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Lever
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
wheeland axle
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Pulley
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Screw
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Compound Machines
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
What does a Simple Machine do?
• A Simple Machine increases the usefulness of a force by changing . . .
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
The Strength of the force
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
How far the force moves
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
The speed
of the
force
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Or,the
directionofthe
force
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
What is Work?Work is performed by applying
a force over a distance.
or
Work = Force X Distance
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Work FormulasIf there are no friction losses (Ideal Machine),
the work effort applied is equal to the work done on the load.
Work in = Work out
or
Force in X Distance in = Force out X Distance out
NOTE: For our purposes, all simple machines will be considered to be “Ideal”.
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
When the force applied to the load is more than the effort, we call that
Mechanical Advantage
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Mechanical AdvantageCan be expressed as a ratio:
MA = Force out Force in
This ratio can also be expressed as:
MA = Distance in Distance out
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Trade offsTo increase the force on the load we must increase the distance traveled by the effort.
If the effort must move farther, it must also move faster.
Sometimes we give up force (MA < 1) to get more distance or speed
Sometimes there is no change in the force (MA = 1) we only want to change the direction of the force.
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
How does an inclined plane work?
The only Simple Machine that does not move
To determine the MA of an inclined plane, compare the length of the ramp to the height.
MA = Length Height
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
How does a wedge work?
Effort is applied to the wedge
Direction is changed by ~90o
Estimate the mechanical advantage by comparing the length of the wedge by its width
MA = Length Width
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Levers
“Give me where to stand, and I will move the earth.” - Archimedes (287-211B.C.)
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Parts of a lever
EffortFulcrum
Load
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
1st class leverAlways changes the direction of the force
May change the strength of the force
May change how far, and how fast, the forces move
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
2nd class lever
Does not change the direction of the force
Increases the force on the load
Effort always moves farther, and faster, than the load
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
3rd class lever
Does not change the direction of the force
Requires MORE effort to move the load (MA < 1)
Purpose is to gain distance and speed
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Definitions:
Fulcrum - The support about which a lever pivots.
Effort Arm - The distance from the applied force or effort to the fulcrum
Load Arm - the distance from the load to the fulcrum
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Estimate the mechanical advantage by comparing the length of the Effort
Arm to the length of the Load Arm
For Example: MA = Effort Arm Load Arm
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Wheel and AxleChanges the strength of the force
Changes how far, and how fast, the load moves
Does not change the direction of the force
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Wheel and AxleEstimate the mechanical advantage by comparing the diameter of the wheel to the diameter of the axle
MA = Wheel diameter Axle diameter
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Pulleys
May increase force on the load
May change distance or speed
May change direction of the force
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Calculating Mechanical advantage of a pulley
Count the number of parts of the rope
supporting the load
MA = 2
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
MA = 3
MA = 4
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Screw
Changes the direction of the force (rotating effort changes to linear motion - approx. 90o)
May change strength of the force
May change the distance and speed
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
d
To estimate the mechanical advantage of a screw:
Determine the pitch ( p) of the screw. This tells you how far the screw moves with one complete rotation.
Find the circumference of the screw. Measure the diameter (d) and multiply by pi (π)
MA = π d p
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Practice
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
The Competition
10 Stations
2 Minutes per station
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Station #1
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
BA
C
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Station #2
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Times Up
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Station #1
Identify the simple machine(s) found in the object displayed
1) Lever A. Yes B. No2) Pulley A. Yes B. No3) Inclined Plane A. Yes B. No4) Screw A. Yes B. No5) Wedge A. Yes B. No6) Wheel and Axle A. Yes B. No
A B
C
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Station #17) Which labeled point is the Fulcrum?
A. AB. BC. C D. Not labeled
8) At which labeled point is force applied to the Load?
A. AB. BC. CD. Not labeled
9) At which labeled point is the Effort applied?
A. AB. BC. C D. Not Labeled
10) Does any part of this machine change the direction of the force?
A. YesB. No
AB
C
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Station #2
Identify the simple machine(s) found in the object displayed
1) Lever A. Yes B. No2) Pulley A. Yes B. No3) Inclined Plane A. Yes B. No4) Screw A. Yes B. No5) Wedge A. Yes B. No6) Wheel and Axle A. Yes B. No
Macomb Elementary Science Olympiad - Feb 2014Simple Machines Workshop - Artie & George Martin
Station #217) Does any part of this machine change the direction of force?
A. YesB. No
18) Is the force on the load less than or greater than the effort applied?
A. Less ThanB. Greater Than
19) Which moves faster?
A. EffortB. Load
20) Which moves farther?
A. EffortB. Load
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