Alex Bishop
Simple Machines
1/9/14
Simple Machines
TEACHER’S INSTRUCTIONS
DESCRIPTION: The lesson uses activities and experiments to demonstrate the types of simple
machines: wedge, screw, lever, pulley, inclined plane, and wheel and axle.
LEARNING GOALS:
Students will testA) The function of a wheel and axle by making and racing toy cars
B) The use of a pulley (fixed pulley demonstration and moveable pulley class activity)
C) The function of a lever (catapult experiment)
Students will observeA) The use of a wedge (apple/butter knife demonstration)
B) The use of a screw (container demonstration)
Students will understandA) The functions of the six types of simple machines
B) Definition of mechanical advantage
RECOMMENDED GRADE LEVELS: K-6th grade, especially 3rd and 4th grade
ESTIMATED TIME REQUIRED: 45 minutes – 1 hour, prep time 45 minutes
KEY CONCEPTS AND DEFINITIONS OF TERMS:
Wedge: A material (often wood or metal) having one thick end and tapering to a thin edge. A wedge
is used to push two objects apart (ex. zipper), cut an object in pieces (ex. knife), or hold objects in
place (ex. doorstop).
Inclined Plane: A flat, sloping surface (ex. ramp). An inclined plane is used to make moving heavy
objects easier; Objects may be pushed up or rolled down.
Screw: An inclined plane (thread) wrapped around a cylinder. A screw is used to hold down objects
(ex. lid on a jar) or hold objects together (ex. screw in a board).
Lever: A board or bar that sits on an object (fulcrum). A lever is used to make moving heavy
objects easier. There are three parts to levers: effort (force that moves lever), load (object the lever
moves), and fulcrum (the point on which the lever moves).
1
Alex Bishop
Simple Machines
1/9/14
Class 1 lever: Fulcrum between effort and load (ex. see-saw)
Class 2 lever: Load between fulcrum and effort (ex. wheelbarrow)
Class 3: Effort between load and fulcrum (ex. catapult)
Pulley: A simple machine made of a wheel and rope; One end of the rope is attached to the load. A
pulley is used to move a load in the opposite direction (fixed pulley) or to move an object more
easily (movable pulley, has mechanical advantage)
Wheel and Axle: An axle (rod) through a wheel. A wheel and axle is used to move objects. The
faster the axle is turned, the faster the wheel spins.
Mechanical Advantage: How many times a machine multiplies force (ex. If you push with 10
pounds and the machine has a mechanical advantage of 2, it’s like pushing with 20 pounds over a
longer distance).
MATERIALS:
1. Empty spool of thread (1), string (~2 ft), small plastic cup (1), rocks (~10), tape, skewer (1)
2. Brooms (2), rope (~5-6 feet), three volunteers
3. Salsa jar or other container with twist turn lid, nail with threaded pattern
4. Popsicle sticks (10 per student), rubber bands, tape, bottle cap (1 per student), beads (1 per
student, any small catapult object works)
5. Apple (1), butter knife (1)
6. Clothespins (2 per student), large can caps (4 per student), soda bottle caps (4 per student),
skewer (1 per student), hammer, nail (1)
7. Large cardboard box(s) to make inclined plane, scissors, tape
SAFETY INFORMATION:
Instructors and students should wear safety goggles at all times.
GENERAL OUTLINE OF PROCEDURES:
1. Demonstration: Fixed Pulleys
2
Alex Bishop
Simple Machines
1/9/14
A. Slide a skewer through the empty thread spool.
B. Tie a piece of string on either end of the skewer and hang from the side of a table or
other surface (must be somewhat far from the ground, must have a lip to allow for
extension of the pulley).
C. Poke holes opposite one another that are just below the lip of the cup.
D. Tie a short piece of string to each side and then tie the strings together to form a triangle
shape (this ensures that the cup does not lean to the right or left).
E. Tie the ends of a long piece of string to the center of the triangle shaped string
attachment on the cup.
F. Add the rocks to the cup.
G. Twist the free string around the spool leaving a small amount at the end for a handle.
H. Place the cup on the ground and pull the suspended string to show the use of the pulley.
2. Class Activity: Movable Pulleys
A. Tie the rope to one of the brooms (broom 1) and wrap the rope around the other broom
(broom 2).
B. Have two students stand ~3 feet apart each holding a broom.
C. Try to keep the brooms separated while the third student pulls on the free end of the
rope. It will be difficult for the student to pull the broomsticks together.
D. Wrap the rope around each of the brooms again. Try to pull the brooms together.
E. Result: The more times the rope is wrapped around the brooms, the easier it is for the
third student to pull the brooms together.
F. Increased mechanical advantage makes it easier for the student to pull the broomsticks
together when the rope is wrapped around more times. The broomsticks and rope form a
pulley system, and the more rope, the less force needed to complete the work.
3. Demonstration: Screws
A. Take out the salsa container with the lid off. Ask students if they are familiar with the
function of a screw type of simple machine.
B. Show students a nail with a threaded pattern.
C. Ask students to watch as you twist on the top of the salsa container.
D. Pre-Lab Question: Ask students what is similar between the motion of the nail with
threaded pattern and the twisting of the salsa lid.
3
Alex Bishop
Simple Machines
1/9/14
E. Explain that both are an example of a screw simple machine. Give the definition as
explained in Key Concepts and Definitions of Terms.
4. Class Activity: Levers
A. Pass out popsicle sticks, film canister lids, masking tape and beads.
B. Stack 6 small popsicle sticks and tie the ends with rubber bands.
C. Position 2 large popsicle sticks on either side of the center of the popsicle stick stack.
D. Secure the recently placed popsicle to the center of the popsicle stick stack with a
crisscrossed rubber band formation. This step may require teacher assistance.
E. Secure the front tips of the popsicle sticks to widen the distance between them.
F. Attach a soda bottle cap with tape.
G. Line up the catapults.
H. Have students write their initials on piece of tape, wrap it around their bead and place the
bead in the catapult.
I. On the count of 3, have students launch the beads. Measure how far the beads traveled.
J. Explain to students that the catapult is an example of a lever.
K. Pre-lab Question: Ask students how they might define a lever.
L. Give the students the definition of a lever (Key Concepts and Definitions of Terms)
M. Ask students to identify the different parts of the lever on the catapult they built.
Suggested Activity: If students are older, discuss Newton’s Laws of Motion. See the link for more
information: http://csep10.phys.utk.edu/astr161/lect/history/newton3laws.html. Additionally, see
this link for ways to demonstrate Newton’s Laws of Motion:
http://www.ehow.com/how_5835702_demonstrate-newton_s-laws-motion.html.
Materials: Hardboiled egg (1), marble (1 per student), paper ball (1 per student), larger version of
the cars made for Wheels and Axles activity (1), Steel balls suspended from a frame (1, see image)
4
Alex Bishop
Simple Machines
1/9/14
5. Demonstration: Wedges
A. Cut the apple using the butter knife.
B. Inform students that many people do not think of a butter knife as an example of a wedge.
C. Ask students to consider what it would be like to try to cut the apple using their hand.
Variations to Try: A doorstop or zipper are also examples of wedges. Doorstops hold the door and
floor together and zippers split the lines of “teeth” apart.
6. Class Activity: Wheels and Axles
A. Prior to class, use a nail and hammer to make holes in the film canister lids.
B. Cut the ends of the skewers so that they are about 5 or 6 inches long.
C. Pass out 2 clothespins, a strip of tape, 4 large caps, and 4 soda bottle caps to each student.
D. Clip the 2 clothespins together by the teeth.
E. Slide the skewers through the swirled metal openings on the clothespins.
F. Slide 2 film canister lids on the ends of each of the skewers.
G. Tape the ends of the skewers to act as hub caps.
H. Wrap tape around the clothespins where they connect to one another. This will help hold
them together. If time permits, decorate the cars.
I. Ask students to give examples of a wheel and axle and explain why they are useful.
J. Explain the wheel and axle (Key Concepts and Definitions of Terms).
7. Class Activity: Inclined Planes
A. Prior to class, create an inclined plane from a large cardboard box.
B. Race the cars built in the previous activity down the inclined plane.
C. Pre-Lab Question: Ask students why an inclined plane can be useful. Have the students
give an example of when they might use an inclined plane.
5
Alex Bishop
Simple Machines
1/9/14
D. Explain the usefulness of an inclined plane (Key Concepts and Definitions of Terms).
CLEANUP: Discarded materials may go in the trash. No chemical cleanup necessary.
1. Collect brooms and rope to reuse.
2. Recycle materials.
3. Save unbroken materials for future experiments. Recycle bottle caps.
4. Discard apple. Rinse and re-use butter knife.
5. Save clothespins and caps for future experiments or allows students to keep cars.
Discard tape.
6. Recycle boxes or save for use in future experiments.
NOTES: See page 9 for student instructions for the class activities: Levers and Wheels and Axles.
See page 10 for student worksheet for 5th and 6th grade.
REFERENCES:
"Baker County 4-H.": Craft Stick Creativity. N.p., n.d. Web. 8 Jan. 2014.
http://4hbakerco.blogspot.com/2011/01/craft-stick-creativity.html (Levers)
Carlson, Liz. Clothespin Button Racer. N.p., n.d. Web. 9 Jan. 2014.
http://almostunschoolers.blogspot.com/2010/12/clothespin-button-racer.html (Wheels and
Axles)
"Inclined Plane." Merriam-Webster. Merriam-Webster, n.d. Web. 09 Jan. 2014.
http://www.merriam-webster.com/dictionary/inclined%20plane (Definition)
"Lever." Merriam-Webster. Merriam-Webster, n.d. Web. 09 Jan. 2014. http://www.merriamwebster.com/dictionary/lever (Definition)
"Powerful Pulleys." Teach Engineering. University of Colorado at Boulder, n.d. Web. 13 Jan. 2014.
http://www.teachengineering.org/view_lesson.php?url=collection/cub_/lessons/cub_simple/
cub_simple_lesson05.xml (Pulleys)
“Pulley." Merriam-Webster. Merriam-Webster, n.d. Web. 09 Jan. 2014. http://www.merriamwebster.com/dictionary/pulley (Definition)
"Screw." Merriam-Webster. Merriam-Webster, n.d. Web. 09 Jan. 2014. http://www.merriamwebster.com/dictionary/screw (Definition)
"Simple Machines." N.p., n.d. Web. 10 Jan. 2014. http://www.mikids.com/Smachines.htm (SeeSaw and pulley images)
6
Alex Bishop
Simple Machines
1/9/14
"The Inclined Plane - Maillardet's Automaton." Understanding Simple Machines. Online Museum
Educators, n.d. Web. 09 Jan. 2014. http://www.fi.edu/pieces/knox/automaton/plane.htm
(Inclined planes encountered daily)
"Wedge." Merriam-Webster. Merriam-Webster, n.d. Web. 09 Jan. 2014. http://www.merriamwebster.com/dictionary/wedge (Definition)
"Wheel and Axle." Merriam-Webster. Merriam-Webster, n.d. Web. 09 Jan. 2014.
http://www.merriam- webster.com/dictionary/wheel and axle (Definition)
7
Alex Bishop
Simple Machines
1/9/14
Fun Sheet (K-3rd)
1. List the six types of simple machines.
2. Give an example of each type of simple machines.
3. What is mechanical advantage (Hint: Think of the pulley)?
8
Alex Bishop
Simple Machines
1/9/14
Student Instructions
Levers
A. Stack 6 small popsicle sticks and tie the ends with rubber bands.
B. Position 2 large popsicle sticks on either side of the center of the popsicle stick stack.
C. Secure the recently placed popsicle to the center of the popsicle stick stack with a crisscrossed rubber band formation.
D. Secure the front tips of the popsicle sticks to widen the distance between them.
E. Attach a bottle cap with tape.
Wheels and Axles
A. Clip the 2 clothespins together by the teeth.
B. Slide the skewers through the swirled metal openings on the clothespins.
C. Slide the film canister lids on the ends of the skewers.
D. Add tape to the ends of the skewers—these will be hub caps.
E. Wrap tape around the clothespins where they connect to one another. This will help hold
them together.
9
Alex Bishop
Simple Machines
1/9/14
Student Worksheet (5th and 6th )
1. What are the six types of simple machines? Give an example for each.
2.What are Newton’s Laws of Motion? (Hint: Think of the activities that we did)
3. What is mechanical advantage?
10