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  • Work, Energy and the SimpleMachines: Lever,Wheel and Axle,

    Pulley

    Instructors Guide

  • Work, Energy and the Simple Machines:LEVER,

    WHEELAND AXLE,PULLEY

    INSTRUCTORS GUIDE

    Written and Produced byJohn Colgren

    United Learning1560 Sherman Avenue, Suite 100

    Evanston, Illinois 60201(800) 323-9084, Fax (847) 328-6706

    http://www.unitedlearning.com

    Published and Distributed by

  • This video is the exclusive property of the copyright holder.Copying, transmitting, or reproducing in any form, or by anymeans, without prior written permission from the copyrightholder is prohibited (Title 17, U.S. Code Sections 501 and506).

    MMI John Colgren

  • LEVER, WHEEL AND AXLE, PULLEY

    Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

    Instructional Notes . . . . . . . . . . . . . . . . . . . . . . . . .1

    Links to Curriculum Standards . . . . . . . . . . . . . . . .2

    Student Objectives . . . . . . . . . . . . . . . . . . . . . . . . .2

    Assessment Tools . . . . . . . . . . . . . . . . . . . . . . . . . .2

    Teacher Preparation . . . . . . . . . . . . . . . . . . . . . . . .3

    Introducing the Program . . . . . . . . . . . . . . . . . . . . .3

    Discussion Questions . . . . . . . . . . . . . . . . . . . . . . .3

    Blackline Master Descriptions . . . . . . . . . . . . . . . .3

    Enrichment Activities . . . . . . . . . . . . . . . . . . . . . . .4

    Answer Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

    Internet Resources . . . . . . . . . . . . . . . . . . . . . . . . .7

    Script of Program Presentation . . . . . . . . . . . . . . . .7

    The purchase of this video program entitles the userto the right toreproduce orduplicate, in whole orin part, this teachers guide and theblackline masterhandouts that accompany it forthe purpose of teach-ing in conjunction with this video, Lever, Wheel and Axle, Pulley. Thisright is restricted only foruse with this video program. Any reproduc-tion orduplication in whole orin part of this guide and the blacklinemasterhandouts forany purpose otherthan foruse with this video pro-gram is prohibited.

    C C This video is closed captioned

  • CLASSROOM/LIBRARYVIEWING CLEARANCE

    This program is for instructional use. The cost of each programincludes public performance rights as long as no admissioncharge is made. Public performance rights are defined as view-ing of a video in the course of face-to-face teaching activities ina classroom, library, or similar setting devoted to instruction.

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    Television/Cable/Satellite Rightsare available. Call yourUnited Learning representative for details.

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    Your suggestions and recommendations are welcome. Feel freeat any time to call United Learning at 1-800-323-9084.

  • LEVER,WHEEL AND AXLE,

    PULLEY

    GRADE LEVELS: 5-8

    INTRODUCTIONThis live-action program is designed for use with the intermediate and middleschool grades (5-8).

    The lever, wheel and axle, and pulley have been grouped together to show howthey are related, but at the same time different from one another. The lever ispresented first and is described as one of the very first simple machines. Thethree main parts of a lever are shown and identified. They include the resistance,the effort or force, and the fulcrum. The three kinds of levers are also describedand illustrated with everyday common tools or devices. The wheel and axle ispresented next and is described as a lever that has been wound up. The largewheel represents the effort arm and the axle represents the resistance arm.Finally pulleys are described. The two kinds of pulleys, fixed and movable, aredemonstrated. Block and tackles, which are combinations of many pulleysworking together are also presented. The mechanical advantage of these simplemachines is calculated.

    INSTRUCTIONALNOTESBefore presenting this lesson to your students, we suggest that you preview theprogram and review this guide and the accompanying blackline master activitiesin order to familiarize yourself with their content.

    As you review the materials presented in this guide, you may find it necessary tomake some changes, additions, or deletions to meet the specific needs of yourclass. We encourage you to do so, for only by tailoring this program to your classwill they obtain the maximum instructional benefits afforded by the materials.

    It is also suggested that the program presentation take place before the entiregroup under your supervision. The lesson activities grow out of the context ofthe program; therefore, the presentation should be a common experience for allstudents.

    1

  • LINKS TO CURRICULUM STANDARDSThis Unit of Study addresses the following National Science EducationStandards for grades 5-8:

    Science as InquiryContent Standard A:

    * Abilities necessary to do scientific inquiry* Understandings about scientific inquiry

    Physical ScienceContent Standard B:

    * Motions and forcesThe motion of an object can be described by its position, direction of motion, and speed.

    * Transfer of EnergyEnergy is a property of many substances and is associated withheat, light, electricity, mechanical motion, sound, nuclei, andthe nature of a chemical. Energy is transferred in many ways.

    Science and TechnologyContent Standard E:

    * Understanding about Science and TechnologyMany different people in different cultures have made and continue to make contributions to science and technology

    History and Nature of ScienceContent Standard G:

    * Science as a Human Endeavor* Nature of Science* History of Science

    STUDENT OBJECTIVESAfter viewing the program and participating in the follow-up activities, stu-dents/participants should be able to... Identify the six simple machines. Identify the main part of a lever. List examples of levers. Describe how a wheel and axle make work easier. Describe the differences between a fixed and movable pulley. Calculate the mechanical advantage of these three simple machines.

    ASSESSMENTTOOLSThis lesson provides you with three different assessment tools. Together they

    2

  • TEACHER PREPARATIONView the program and review the accompanying activities. Duplicate any black-line masters you wish to distribute. If you plan to use the Video Quiz, whichimmediately follows the program presentation, you may wish to have copies ofthe quiz ready to distribute at the completion of the program. Also, plan to pausethe program between questions if students require more time.

    INTRODUCING THE PROGRAMAsk the class to think of all the different kinds of tools and machines that areused in our modern world. Ask for some examples such as hammers, hugecranes, etc. Then tell the students that all the machines we use today are basedon six simple machines that were discovered and used thousands of years ago.

    VIEW THE PROGRAMViewing time for this program is 10 minutes. The video quiz that follows thepresentation will take about 5 minutes when you build in pauses for recordinganswers.

    DISCUSSION QUESTIONSYou may wish to conduct a discussion after viewing the program based on thefollowing:This program concentrates on the lever, wheel and axle, and screw. Ask studentsto think of examples of each of those simple machines. Why were these threesimple machines grouped together? (They are related to each other)

    BLACKLINE MASTER DESCRIPTIONSThis program contains eleven blackline masters that can be used to reinforceideas and information presented in the program. Blackline Master #1: Pre-Test provides a way of finding out how much stu-dents know about the material covered in this lesson before you present it.Student scores on the Pre-Testcan be compared with their scores on the finalPost-TestBlackline Master#11.

    make it possible to follow closely the progress of your students and to judge theirmastery of the subject matter.

    The Pre-Test Blackline Master#1can be used to get some idea of studentsunderstanding of the topic before the program is presented.The Post-Test, presented as Blackline Master#11, can be used as a final test forthe lesson.

    The Video Quizand its accompanying answer sheet (Blackline Master#2)canbe used as a follow-up to the program.

    3

  • Blackline Master #2: Video Quizis to be used at the end of the program. Atthe completion of the program, there is a short quiz. The narrator will read thequestions which are displayed on the screen. Students can use Blackline Master#2: Video Quiz to record their answers. Answers to the questions are providedin the Answer Key section of this teachers guide.

    Blackline Master #3: Vocabulary asks students to match terms in column Awith definitions in column B.

    Blackline Master #4: Levers asks students to identify the fulcrum, resistance,and effort for various levers.

    Blackline Master #5: Levers - Three Classes asks students to identify variouslevers as first, second, or third - class levers.

    Blackline Master #6: Two Arms contains information about calculating miss-ing information from word problems dealing with levers.

    Blackline Master #7: Mechanical Advantage of a Lever provides informationabout how to calculate the mechanical advantage of a lever.

    Blackline Master #8: Mechanical Advantage of a Wheel and Axle is a work-sheet that explains how to determine the mechanical advantage of a wheel andaxle. Students are asked to measure some objects at home and determine themechanical advantage of those wheel and axles.

    Blackline Master #9: Kinds of Pulleys is an experiment with two parts. PartA describes how to set up a fixed pulley and Part B describes how to set up amovable pulley.

    Blackline Master #10: Mechanical Advantage of Pulleys describes how themechanical advantage of a pulley is calculated.

    Blackline Master #11: Post-Test. This is the post-test for this program.

    ENRICHMENTACTIVITIES Have some students find out about the evolution of the bicycle. How has itchanged over the years and why?

    ANSWER KEY Blackline Master #1: Pre-Test

    1. lever, wheel and axle, pulley, inclined plane, wedge, screw

    4

  • 2. fulcrum, resistance, effort3. fixed and movable4. A wheel and axle is like a lever wound up.5. When a machine has a mechanical advantage it means the machine makes

    the work easier and therefore a small effort can be used to accomplish a greatertask.

    6. The mechanical advantage of a movable pulley is determined by the num-ber of supporting ropes.

    7. The mechanical advantage of a wheel and axle is calculated by dividing thediameter of the wheel by the diameter of the axle.

    8. A block and tackle is a combination of two or more pulleys used together.9. 20 pounds

    10.Energy is the ability to do work

    Blackline Master #2: Video Quiz1. c2. a3. a4. d5. a6. Energy is the ability to do work7. A fixed pulley is stationary and used only to change the direction of effort.

    A movable pulley is attached to the resistance or load and moves with it. A mov-able pulley provides a mechanical advantage.

    8. A block and tackle is a combination of two or more pulleys.9. lever, wheel and axle, pulley, inclined plane, wedge, screw

    10.The location of the fulcrum, resistance arm, and effort arm

    Blackline Master #3: Vocabulary1. c2. e3. g4. a5. f6. b7. h8. d

    Blackline Master #4: Leverspliers - resistance is the claws, the fulcrum is at nut, effort is in handleshammer pulling a nail - resistance is nail, fulcrum is at hammer head where ittouches wood, hammer handle is the efforthammer nailing - hammer head is resistance, hand is effort and the fulcrum is

    5

  • below the hand on the handlenutcracker - nut is resistance, fulcrum is nut and bolt, effort is handles of nut-crackerbroom - resistance is what broom is sweeping, hands on handle are effort, ful-crum is above handsmoving a rock with a board - rock is resistance, end of board is effort and ful-crum is log.

    Blackline Master #5: Levers - Three Classespliers - first-classbroom - third-classnutcracker - second-classhammer nailing - third-classhammer pulling nail - first-classmoving rock - first-class

    Blackline Master #6: Two Arms1. 37.5 newtons2. 6 feet3. 125 newtons

    Blackline Master #7: Mechanical Advantage of a Lever1. M.A. = 22. M.A. = 23. M.A. = 4

    Blackline Master #8: Mechanical Advantage of a Wheel and AxleAnswers will vary

    Blackline Master #9: Kinds of PulleysObservations Part A: Answers will vary but will be the same for one and two.Part B: The reading on the scale should be one half the weight of the book.

    Blackline Master #10: Mechanical Advantage of PulleysM.A. = 4 five pounds of effort to lift 20 pound objectM.A. = 6 12.5 newtons of effort to lift 75 newtons

    Blackline Master #11: Quiz1. lever, wheel and axle, pulley, inclined plane, wedge, screw2. a. turning point on a lever

    b. the load on a leverc. a push or pulld. the length of the effort arm on a lever

    6

  • e. the length of the resistance arm on a lever3. The location of the fulcrum, resistance, and effort.4. pliers - claws resistance, handles effort, nut and bolt fulcrum

    hammer - nail resistance, hand on handle effort, head of hammer fulcrumfishing pole - fish resistance, effort in hands, fulcrum below hands

    5. 25 pounds of effort6. The diameter of the wheel is divided by the diameter of axle.7. the number of supporting ropes8. a combination of two or more pulleys9. A fixed pulley doesnt provide any mechanical advantage.

    10.Energy is the ability to do work

    INTERNET RESOURCEThe following website may be a valuable source of additional information toreinforce the objectives of this lesson:

    1.) Work, Energy and the Simple Machines at http://www.unitedlearn-ing.com will be designed as an electronic learning module specifically correlat-ed to this Unit of Study. It will support and enhance the content and ideas pre-sented in this series of vide tapes. This will add a new dimension to instructionand learning.

    Lever, Wheel and Axle, PulleyScript of Narration

    This man is straining to lift the weights on the exercise equipment. The weightsaren't moving, so to a scientist this man has done no work.

    Work is only accomplished when an object is moved a distance. A force is need-ed and to provide the necessary force energy is required.

    Energy is the ability to do work. In our machine orientated world we have manytools and devices that help to get work done easier or faster, but as complicatedas so many of these machines seem they are all based on just six simple machinesthat were developed a very long time ago.

    The six simple machines are the lever, wheel and axle, pulley, inclined plane,wedge, and the screw. Today we'll take a close look at three of these simplemachines; the lever, wheel and axle, and the pulley.

    The lever was one of the first simple machines. It is made up of two main parts.A bar that rotates or turns around a support point called a fulcrum. A lever is usedto move a resistance or load. The force necessary to move a load doesn't have toequal the weight of that load.

    7

  • The idea is to try and have the resistance close to the fulcrum and the effort asfar from the fulcrum as possible. The longer the effort arm the greater the lever-age; which means a small effort is required to produce a great force.

    Notice that the adult is easily lifted with one hand. The effort moves through agreat distance while the resistance only moves a short distance. The advantageis that the effort needed to lift the load is much reduced.

    There are actually three kinds or classes of levers.

    This board is being used as a first-class lever. The fulcrum is located somewherebetween the resistance and the effort. A nutcracker is an example of a second-class lever. This time the resistance isbetween the fulcrum and the effort.

    A third-class lever is set up with the effort between the resistance and fulcrum.This rake is an example of a third-class lever.

    If a hammer is being used to drive a nail what kind of lever do you think it rep-resents?

    The effort is the person's hand, the resistance is the hammer head.

    The fulcrum is below the hand so the effort is between the resistance and the ful-crum. It is a third-class lever.

    What kind of lever is a hammer that is being used to pull a nail?(pause)

    It's a first-class lever.

    The person's hand is providing the effort, the nail is the resistance and the ful-crum is located somewhere between the effort and resistance.

    A crowbar is used to pry two boards apart. The crowbar is being used as a lever.Think of where the resistance is the effort and the fulcrum. It's a first-class lever.The fulcrum is between the effort and resistance.

    The wheel was one of the most important inventions of all times. No one knowswhere the wheel was invented, but there is evidence that people living 6,000years ago used wheels.

    The wheel and axle is related to the lever. It is like a lever that has been woundup.

    8

  • The larger wheel represents the effort arm and the axle represents the resistancearm. The bigger the wheel compared to the axle the easier it is to use the wheeland axle.

    A steering wheel makes it easy to steer a car.

    A truck or a bus has a bigger wheel to help steer the larger vehicle. Skateboards, in line skates, and bicycles all use wheels and axles.

    A door knob is another common example of a wheel and axle. It is easy to opena door because the door knob is like a wheel.

    If we remove the door knob we can see the axle that operates the door clasp.

    A bicycle uses the wheel and axle idea to make peddling easier. The peddles turnin a wide circle. The chain connects the peddle with the rear sprocket, which issmaller, and therefore turns many times each time the peddle goes around once.

    Another simple machine that is related to the wheel and axle is the pulley. Thepulley has a wheel and axle built into it. There are two kinds of pulleys.

    One is called a fixed pulley which means the pulley is attached to something.

    The object being lifted is attached to one end of a rope. The other end of the ropeis fed through the pulley, and then a force is used to pull on the rope. The fixedpulley doesn't make lifting easier; it changes the direction of effort.

    The other kind of pulley is the movable pulley. In this case the pulley moveswith the object being lifted. Because of the way the rope is used it takes onlyhalf the effort to lift the load.

    For example, this block of wood weighs 240 grams, but when lifted by a mov-able pulley the effort needed is half as much.

    A combination of pulleys used together is called a block and tackle. A block andtackle can be used to lift heavy objects.

    When a machine makes work easier because it multiplies the effort being appliedwe say the machine is providing a mechanical advantage.

    To find the mechanical advantage of a lever you need to measure the length ofthe effort arm and the length of the resistance arm. Then, divide the effort armlength by the resistance arm length.

    9

  • Remember lifting the adult with the first class lever? Let's measure the effort andresistance arms. The adult who is the load in this case is 1 meter from the ful-crum. The effort arm is four meters long. If we divide the effort effort arm bythe resistance arm we find the mechanical advantage is four.

    Another way of thinking of the mechanical advantage of four is to take the adultsweight, which is 180 pounds, and divide it by four. The answer is 45 pounds ofeffort to lift the 180 pound adult.

    The mechanical advantage for a wheel and axle is determined by dividing thediameter of the wheel by the diameter of the axle.

    Let's calculate the mechanical advantage of this doorknob. The diameter of thewheel part is five centimeters. The diameter of the axle is two centimeters.Therefore the mechanical advantage is two and a half.

    It's very easy to determine the mechanical advantage of a pulley setup. Themechanical advantage is equal to the number of supporting strands. So a mov-able pulley has a mechanical advantage of two while a fixed pulley has amechanical advantage of one.

    When more pulleys are added the mechanical advantage increases dramatically.What this means is that if a block and tackle set up has four supporting strandsits mechanical advantage is four. The amount of effort needed to lift an object is1/4 of the objects weight. If the object weighs 40 grams it will take only tengrams of effort to lift it.

    The six simple machines have been important contributors to our advancementthrough the ages. However, not every application has succeeded. Take forinstance this invention:

    You probably recognize the bike. What you probably didn't notice was the rock-et strapped to it.

    This inventor felt a rocket propelled bicycle would revolutionize our means oftravel.

    I guess he wasn't right.

    Now it's time for a video quiz. There will be ten questions. The first five willbe multiple choice and the last five are fill-in the blank or short answer.

    10

  • Question number one.The turning point of a lever is called the ___________.

    a. resistanceb. effortc. fulcrumd. arm

    Question number two.The load or object being moved on a lever is called the ________.

    a. resistanceb. effortc. fulcrumd. arm

    Question number three.The mechanical advantage of a wheel and axle is determined by _____

    a. dividing the diameter of the wheel by the diameter of the axle.b. dividing the axle radius by the wheel radius.c. measuring the length of the effort arm.d. dividing the resistance arm by the effort arm.

    Question number four.How do we calculate the mechanical advantage of a movable pulley?

    a. Divide the length of the effort arm by the length of the resistance arm.b. Divide the wheel radius by the axle radius.c. Measure the length of the effort arm.d. Count the number of supporting strands of rope.

    Question number five.How do we calculate the mechanical advantage of a lever?

    a. Divide the length of the effort arm by the length of the resistance arm.b. Divide the wheel radius by the axle radius.c. Divide the length of the resistance arm by the length of the effort arm.d. Divide the weight of the load by the effort arm.

    Question number six.What is energy?

    Question number seven.How is a fixed pulley different from a movable pulley?

    Question number eight.What is a block and tackle?

    11

  • Question number nine.Name the six simple machines.

    Question number ten.There are three kinds of levers. What makes them different from each other?

    12

  • DIRECTIONS: Answer the following questions in the space provided.

    1. What are the three parts of a lever? _____________ _____________ ______________

    2. There are three classes, or kinds, of levers. How are they different from each other?

    3. What is the resistance arm of a lever?

    4. What is the effort arm of a lever?

    5. How has the wheel and axle made work easier for humans?

    6. Name three examples of a wheel and axle in operation.

    7. There are two kinds of pulley systems. One is called a fixed pulley and the other is called a movable pulley. How are they different?

    8. A pulley at the top of a flagpole is used to raise a flag. Of what kind of pulley is that anexample? ________________

    9. A series of pulleys used together is called a _______ and __________.

    10. Give three examples of pulleys in use.

    1 Name

    Discovering Simple Machines: Lever, Wheel and Axle, PulleyPRE-TEST

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley 2001 Colgren Communications

    All rights to print materials cleared for classroom duplication and distribution.

  • Name _______________

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley VIDEO QUIZ

    This is the video quiz for the video called Lever, Wheel and Axle, Pulley. Questions will appear at the end of the video. Write your answers on this sheet of paper.

    1. The weight of the object being moved on a lever is called the ____________. a. fulcrum b. force or effort c. resistance d. arm

    2. The pivoting or turning point of a lever is called the ____________.

    a. fulcrum b. force or effort c. resistance d. arm

    3. The push or pull on a lever is called the ____________. a. fulcrum b. force or effort c. resistance d. arm

    4. A first-class lever has the fulcrum between the resistance and effort. Which of these is a

    first-class lever? a. broom b. fishing pole c. scissors d. baseball bat

    5. If the fulcrum is at one end of a lever, and the resistance is at the other end with the effort

    or force between them, it is a third-class lever. Which of these is a third-class lever? a. broom b. hammer pulling a nail c. scissors d. pliers

    6. The wheel and axle is related to the lever because it is like a lever wound up. The large

    wheel is like what part of the lever? a. fulcrum b. resistance arm c. effort arm d. load

    7. The axle or smaller wheel of the wheel and axle is like what part of the lever?

    a. fulcrum b. resistance arm c. effort arm d. none of these

    8. What is a fixed pulley? 9. When using a fixed pulley, the amount of effort needed to lift a load is equal to the weight

    of the load. What does the fixed pulley do? a. Make work easier. b. Change the direction of the effort c. Help support the load. 10. How does a movable pulley make work easier?

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley 2001 Colgren Communications All rights to print materials cleared for classroom duplication and distribution.

    2

  • Levers were probably one of the very first machines.

    There are three parts to every lever. One part isthe object or weight being moved. It is calledthe resistance. A push or pull is needed tomove the resistance. This push or pull is calledthe force or effort. The third part of the leveris called the fulcrum. It is the point on thelever where direction and movement changes.

    3 Name

    Discovering Simple Machines: Lever, Wheel and Axle, PulleyLEVERS

    DIRECTIONS: Label the parts of each lever shown. Each lever will have a fulcrum, aresistance, and a force.

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley 2001 Colgren Communications

    All rights to print materials cleared for classroom duplication and distribution.

  • DIRECTIONS: Do the following experiment to find out more about levers. Answer the ques-tions in the Observations section.

    Purpose: To demonstrate the principle of a lever.

    Materials: 1. A ruler2. three pennies 3. a pencil

    Procedures:1. Lay the pencil on the flat surface of your desk.2. Balance the ruler on the pencil so that it resembles a seesaw. The ruler is

    balanced when both ends are off the table or desk top. Make observations.3. Place a penny on one end of the ruler.4. Place another penny on the other end of the ruler to balance it again. Make

    observations.5. Place a third penny on top of one of the pennies already on the ruler.6. Try to balance the ruler by moving the pennies. The pennies must stay on

    their side of the ruler and the double penny set-up must stay as one penny on top of the other.

    Observations:1.When you first balanced your ruler on the pencil, what was the reading on the ruler above the pencil or fulcrum?

    2. How did you balance the ruler when there was a penny on each side of the fulcrum?

    3. How did you solve the problem of balancing two pennies with one?

    4 Name

    Discovering Simple Machines: Lever, Wheel and Axle, PulleyLEVERS - TWO FOR ONE

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley 2001 Colgren Communications

    All rights to print materials cleared for classroom duplication and distribution.

  • There are three classes or kinds of levers. They are called FIRST-CLASS, SECOND-CLASS,and THIRD-CLASS LEVERS. What makes one class of lever different from another is wherethe force, resistance, and fulcrum are located. Here are some examples:

    5 Name

    Discovering Simple Machines: Lever, Wheel and Axle, PulleyLEVERS - THREE CLASSES

    DIRECTIONS: Identify the levers below as first-class, second-class, or third-class levers.

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley 2001 Colgren Communications

    All rights to print materials cleared for classroom duplication and distribution.

    First-class leverIn this case the fulcrum is located between the force and resistance. Aseesaw is a good example of a first-class lever.

    Second-class leverA second-class lever is set-up so that the resistance is between theforce and fulcrum. A wheelbarrow is a second-class lever.

    Third-class leverIn the case of a third-class lever, the force is between the resistanceand the fulcrum. A fishing pole is a good example.

  • A wheel and axle is a simple machine that acts as a lever. The steer-ing wheel on a car is a perfect example of a wheel and axle. Thelarge steering wheel is attached to a smaller rod called the steeringcolumn. The force from the steering column is used to turn thewheels so that the car can be driven properly. That force is a great

    force because the steering column acts like an axle. The steering wheel is large and turns easi-ly in a persons hands. The steering column, which is the axle part of this simple machine, ismuch smaller but is attached to the steering wheel, so when the steering wheel is turned, thesteering column also turns. The steering column turns with much more force than the steeringwheel so that the heavy front tires can be turned and controlled. The larger the steering wheel,the greater the force on the steering column or axle.

    Questions: 1. Why do trucks have such large steering wheels?

    2. Why do ocean liners and other large ships have large steering wheels?

    6 Name

    Discovering Simple Machines: Lever, Wheel and Axle, PulleyWHEEL AND AXLE

    There are examples of wheels and axles all around you. Everyday you use this simplemachine.Directions: Tell how each of the things listed below is an example of a wheel and axle. Alsotell how it makes work easier or faster.

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley 2001 Colgren Communications

    All rights to print materials cleared for classroom duplication and distribution.

    DOOR KNOBSCREWDRIVER - Used toloosen or tighten a screw

    HAND DRILL PENCIL SHARPENER

  • Gears are like wheels with notches or teeth on them. Gears can be used to change the direc-tion of effort, slow or speed things up, or turn many things at once. Gears are used on tenspeed bikes and in watches or clocks.

    Purpose: To demonstrate how gears work.

    Materials: 1. brass fastener2. construction paper or cardboard

    Procedures:1. Cut out the gear patterns at the bottom of the page.2. Trace them onto the construction paper or cardboard3. Gear B has dotted marks to show where you should fold the teeth up.4. Cut a hole in the center of each gear and pass a brass fastener through

    these holes.5. Pass the brass fastener through a second rectangular sheet of construction

    paper or cardboard.6. Arrange the gears so their teeth interlock.

    Part A1. Set up the gears as shown in diagram A.2. Turn gear A clockwise.3. How does gear B turn? __________

    Part B1. Make additional gears A and B.2. Set up as shown in diagram B.3. Turn gear A clockwise.4. How does the end gear turn? _______

    7 Name

    Discovering Simple Machines: Lever, Wheel and Axle, PulleyGEARS

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley 2001 Colgren Communications

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    Diagram A

    Diagram B

    A B

  • There are two kinds of pulleys. You can use some simple objects to set up demonstrations ofeach of these pulley systems.

    Materials: 1. Two single pulleys (from hardware store or science supply)2. twine3. three heavy books4. a spring scale5. desk6. ruler

    Part One: FIXED PULLEY1. Place the ruler on the edge of the desk and lay two of the books on it so that

    the ruler will stay in place.2. Take a pulley and attach it to the ruler with twine. The pulley should be

    hanging freely under the ruler.3. Tie twine around the remaining book and weigh the book with the spring

    scale.4. Feed twine through the pulley wheel. Tie one end of the twine to the book.

    Tie the other end of the twine to the spring scale.5. Pull the spring scale to lift the book. Record the reading on the scale.

    Part Two: MOVABLE PULLEY1. Repeat step 1 under Part One.2. Tie a long piece of twine to the end of the ruler.3. Feed the twine through the pulley wheel.4. Attach the book to the pulley and the spring scale to the end of the twine.5. Lift the book by pulling on the twine. Record the spring scale reading.

    Observations:Part One1. What was the weight of the book to be lifted?2. What was the reading on the spring scale as you lifted the book with the

    pulley?

    Part Two1. What was the reading on the spring scale as you lifted the book with this

    set-up?

    8 Name

    Discovering Simple Machines: Lever, Wheel and Axle, PulleyKINDS OF PULLEYS

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley 2001 Colgren Communications

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    Part One Part Two

  • DIRECTIONS: You can see the help a pulley provides by perform-ing the following experiment. Answer the questions in theObservation and Conclusion sections.

    Purpose: To show the advantage of using a pulley.

    Materials: 1. two broomstick handles2. rope or clothesline at least eight feet long3. two helpers

    Procedure: 1. Ask each of your helpers to face each other holding a broomstickwith both hands out in front of them.

    2. Tie one end of the rope to one of the broomsticks.3. Weave the rope around the two broomsticks a number of times and

    then back away while holding your end of the rope.4. Pull your end of the rope so that everything tightens.5. Tell your friends to pull their broom handles apart.6. While theyre pulling on the broomsticks, you should pull on the

    rope youre holding.

    Observations: What happened?

    Conclusions: Why did things happen the way they did?

    9 Name

    Discovering Simple Machines: Lever, Wheel and Axle, PulleyPULLEYS

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley 2001 Colgren Communications

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  • DIRECTIONS: Answer these questions in the space provided.

    1. Name the six simple machines. __________________ __________________________________ ________________ ________________ ________________

    Give a definition for the following terms:2. effort ___________________________________________________________

    3. resistance ________________________________________________________

    4. fulcrum __________________________________________________________

    5. There are two types of pulleys. What are they called and how are they different?

    6. How does a lever help people?

    7. Name some examples of wheel and axle simple machines found around schooland home.

    8. Give at least five examples of levers.

    9. Give at least five examples of how pulleys are used.

    10. There are three classes of levers. What is it that makes the classes of levers different from each other?

    10 Name

    Discovering Simple Machines: Lever, Wheel and Axle, PulleyPOST-TEST

    Discovering Simple Machines: Lever, Wheel and Axle, Pulley 2001 Colgren Communications

    All rights to print materials cleared for classroom duplication and distribution.