OUTREACH : HANDS-ON WORKSHOPS : Simple Machines

Learn the golden rule of “force for distance” by testing it yourself. Discover how simple machines reduce effort to make work easier.

Michigan Grade Level Content Expectations, Science, 2007

Simple Machines Pre-visit Vocabulary

Distance: The measurable amount something moves.

Effort: Force or energy you put into moving something.

Energy: Energy is the capacity for doing work. Forms of energy include light, heat and electricity.

Force: A push or pull.

Fulcrum: Pivot point of a lever; place where a lever turns.

Inclined Plane: Simple machine that is any sloped surface.

Lever: Simple machine that consists of a bar that rotates on a fulcrum.

Load: Mass that is being moved.

Machine: Device that multiplies your force or changes the direction of the force.

Newton: Unit used to measure force.

Pivot: To turn.

Pulley: Simple machine that is a wheel and axle with a groove to hold a rope.

Screw: Simple machine that is a combination of a cone and an inclined plane.

Simple Machine: Any object that makes work easier by trading force for distance.

Spring scale: Measuring device used to determine amount of force used.

Wedge: Simple machine that is a moving inclined plane.

Wheel & axle: Simple machine made of a bar on which a round object turns.

Work: Moving something.

Simple Machines Post-visit Activity

Post-visit activities provide your students with an opportunity to review workshop-presented concepts and introduce related subjects. Below you will find a classroom extension activity and a list of suggested resources for further exploration. We hope that you enjoyed our Outreach Hands-On Workshop, and we look forward to visiting your students again!

Hands-on Activity: Machine Mobiles

This activity is not only an art project, but illustrates the concept of a first class lever as well. Remember, a first class lever is a lever with the fulcrum located in the middle, between the load and the force being applied. Teeter-totters and scales are first class levers. A first class lever is in balance when the load is equal on either side of the fulcrum — just what you need to create a mobile!

This is a great cooperative learning opportunity since students will need assistance from one another when it comes to tying the thread to the wire and balancing the mobiles.

Materials

• Clear tape
• Crayons
• Poster board
• Thread
• Wire cutters

Per student:

• Pictures of models of machines (draw your own or use those provided)
• Wire hangers (one per student)

Procedure

1. Draw color, and cut out 4 machines using poster board. Or, use the pictures provided and glue them to poster board.
2. Cut the hangers into 3 pieces — 1 short, 1 medium, and 1 long, straight piece. Throw the rest of the hanger away. (The best way to do this may be to have the teacher go around the room with wire cutters while the students are working on their machines).
3. Tape a piece of thread about 6-8 inches long to the approximate top and middle of each machine.
4. Tie a machine to one end of shortest wire. Tie another machine to the other end of that wire. Every time you make a knot, be sure to wrap the thread around the wire about 3 times before making a double knot.
5. Tie one machine each to the ends of the two other wires.
6. Begin assembling the mobile from the bottom up. Each mobile will need 3 more pieces of thread about 6-12 inches long. Tie one of the pieces of thread to the point you predict will balance the shortest wire. Hold the short wire with its two machines up by this thread and see if it balances. Slide the knot back and forth until it does.
7. Tie the loose end of this thread tightly to the free end (the end without a machine tied to it) of the middle-length wire. Take another loose piece of thread and tie it tightly to this medium-length wire, just about where you think it will balance (balancing it in the tip of your finger might help you to find the right spot).
8. Tie the loose end of that thread tightly to the free end of the longest wire.
9. Use your last piece of loose thread to hang the mobile by tying it to the balance point of the longest wire.
10. Have a friend help you to balance the whole mobile by having your partner hold it up while you carefully slide the knots back and forth to make it balance. ALWAYS START FROM THE BOTTOM and work up!
11. If your knots slide around a lot, try putting a very small piece of tape over them.
12. Hang your mobile up and enjoy!

Suggested Resources

Books

Battcher, D., Erickson, S., Martini, K., Rogers, C., Shennan, W., and Wiebe, A. Machine Shop. AIMS Education Foundation, Fresno, CA. 1993.
Dahl, Michael. Inclined Planes. Bridgestone Books, Mankato, MN. 1996.
Dahl, Michael. Levers. Bridgestone Books, Mankato, MN. 1996.
Potter, Jean. Science in Seconds for Kids. John Wiley and Sons, Inc., New York. 1995
St. Andre, Ralph. Simple Machines Made Simple. Teacher Ideas Press, Englewood, CO. 1993..
Tolman, Marvin N. Hands-On Physical Science Activities for Grades 2–8. Parker Publishing Company, Inc., NY. 1995.
West, David. Wheels, Pulleys, and Levers. Shooting Star Press, New York. 1993.

Internet

Project Smart 96
The Franklin Institute Online
Hands-on Technology Program
Museum of Science