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