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Ch. 12 Lesson 3 How do simple
machines affect work?
workWhen a force moves an
objectNot done when the
position of an object does not change
Examples of work
When work is doneActivity Work
Thinking about a math problem
Turning a jump rope
Holding a puppy
Lifting a puppy
Pulling on a locked door
Opening an unlocked door
Trying to scoop rock-hard ice cream
When work is doneActivity Work
Simple Machineshelp make work
easierdon’t lessen amount
of work
6 kinds of
inclined planeslanting
surface that connects a lower level to a higher level
inclined plane
wedge made up of 2
slanted sides that end in a sharp edge
used to split, cut or fasten things
wedge
screw inclined plane
wrapped around a center post
used to hold things together & to raise & lower things
screw
leverstiff bar that
rests on a support
used to lift & move things
lever
wheel and axle ex: doorknob wheel=knob axle=post that
attaches to its center
wheel and axle
wheel and axle
faucet handle
pulley changes the
direction of motion to which a force is applied
pulley
Simple Machines Game Simple Machines game http://staff.harrisonburg.k12.va.us/%7Emwampole/
1-resources/simple-machines/index.html http://sunshine.chpc.utah.edu/javalabs/java12/
machine/index.htm http://www.galaxy.net/~k12/machines/index.shtml http://www.quia.com/pages/
hostetterscience.html#simple How can we move our principal game
Simple Machines Activities http://atlantis.coe.uh.edu/archive/science/scie
nce_lessons/scienceles1/finalhome.htm http://www.mikids.com/Smachines.htm http://teacher.scholastic.com/dirtrep/simple/
index.htm
The 6 Simple Machines1. Lever 3. Pulley
4. Wheel and Axle 6. Wedge5. Screw
2. Inclined Plane