Simple Machines: Can You Go The Distance?

Transcription

1 TEACHER GUIDE Simple Machines 60 Minute Physical Science Lesson Science- to- Go! Program Grades: 5-8 Simple Machines: Can You Go The Distance? Description They might be called Simple Machines, but the concept of trading force for distance can be anything BUT simple for students to grasp. Our Science Instructors will challenge your class to demonstrate the use of levers, gears, inclined planes, screws, pulleys and wedges while explaining how each item reduces the amount of force necessary to move a specific mass. Objectives Demonstrate that simple machines trade force for distance. Demonstrate how a force on an object can change its direction. Follow scientific procedure to predict outcomes and test hypotheses using simple machines. Identify the simple machines needed to make up a variety of common household tools. Ohio s Learning Standards Grade 5: Physical Science Light, Sound, and Motion The amount of change in movement of an object is based on the mass of the object and the amount of force exerted. Grade 6: Physical Science Matter and Motion There are two categories of energy: kinetic and potential. An object s motion can be described by its speed and the direction in which it is moving. Grade 8: Physical Science Forces and Motion Forces between objects act when the objects are in direct contact or when they are not touching.

2 How to Set Up Your Room Please have student desks clear before the program begins. Please provide an empty desk or small table for the museum educator to set up display items. If booking multiple programs, transitions will be easier if museum staff sets up in only one location. Additional set- up requirements: o Divide students into 6 groups. o Students will each need a pencil and a copy of the attached Simple Machines worksheet. Introduce the vocabulary and additional resources provided below. Vocabulary distance how far the load is moved force a push or a pull on an object friction a resisting force caused when two surfaces move against oneother fulcrum the pivot about which a lever turns inclined plane a slanted surface whose angle affects the force needed to move a mass along the surface kinetic energy the energy of motion lever - A stiff bar that rests on a middle support (fulcrum) that is used to lift or move a load load what is being moved machine a tool that makes work easier newton the unit of force required to accelerate a mass of one kilogram one meter per second per second potential energy - The energy of a particle or system of particles derived from position, or condition, rather than motion. A raised weight, coiled spring, or charged battery has potential energy pulley - A simple machine that used grooved wheels and a rope to raise, lower, or move a load resistance a force that tends to oppose or slow down a motion simple machine a simple device, such as a lever, pulley, or inclined plane; a machine without moving parts spring scale a balance that measures weight by the tension on a helical spring work when a force that is applied to an object moves that object

3 Extension Activities Simple Machine Scavenger Hunt Pick one of the simple machines, or all of them, and look for examples around the school building. Students can also do this activity at home with their family. Keep a running list of the examples of simple machines identified. Create a classroom chart or bulletin board of your scavenger hunt results. Consider creating a bar chart of common examples or a map illustrating where simple machines can be found around the classroom. Design a Compound Machine Tell students that they are going to be engineers and will be designing, building, and demonstrating a compound machine that will move some object in the classroom (be as creative as you d like with this). Have students work in groups of 3-4. Groups will have to use at least 3 simple machines in their compound machine. Have groups draw out their designs. After presenting to you, let them construct their machine. Have a variety of boards, wedges, pulleys, levers, gears, and screws available for them to build their machine. Allow them to experiment and perfect their machine. Encourage them to make the most efficient machine by testing with spring scales the amount of force necessary to move the object. Have each group of students demonstrate their final project to the rest of the class. Online Resources for Teachers and Students Click the link below to find additional online resources for teachers and students. These websites are recommended by our Museum Educators and provide additional content information and some fun, interactive activities to share with your class. CMNH Educators regularly review these links for quality. Web addresses often change so please notify us if any links have issues. Cleveland Museum of Natural History

4 Educator Resource Center (ERC) The Educator Resource Center offers educator workshops, thematic teaching kits, animal dioramas, and more for loan to area teachers. Contact the ERC at for information on individual or school membership. Visit the Museum s ERC website for more information on workshops Hours o Monday through Friday, 1 to 5 PM o Wednesday, 1 to 6 PM o Saturday, 9 AM to 2 PM Materials for Loan If you re interested in additional resources be sure to check out the following ERC materials or browse ERC materials online at Related ERC kits for this topic include: Simple Machines: This kit contains hands- on materials to investigate and experiment with pulleys, levers, and wheels and axles. Force and Motion: This kit contains a variety of items for students to work as they experiment with forces and motion. NASA Rocketry: Your students will blast off into a multidisciplinary world of science, technology, engineering, and mathematics. Learn how to build and launch water bottle rockets and examine the composition of various materials. Find out about astronauts through fact and playing cards and explore a scale model of NASA's Saturn V rocket.

5 INCLINED PLANES An inclined plane is a simple machine that is used to move objects to a higher level. 1. How many Newtons does the scale read with the car on the low ramp? N 2. How many Newtons does the scale read with the car on the steep ramp? N 3. Complete this sentence: The the ramp, the force it takes to pull the mass up the ramp. WEDGES A wedge is a simple machine that is used to cut or separate things. Wedges are two inclined planes joined together. 1. Over the picture of each wedge, record how many washers it took to sink the wedge into the sand. 2. Compare the angle of the wedge with the amount of washers it took to sink the wedge into the sand. Complete this sentence: The the wedge, the force it takes. SCREWS Screws are a special type of inclined plane. They are inclined planes that are wrapped around a pole. Screws are used to hold two things together. 1. Which triangle has the steepest slope? BLACK RED 2. Which triangle has the shallower slope? BLACK RED 3. With the flags rolled up, which has more turns? BLACK RED 4. Match the screw to the inclined plane that it came from: 5. Based on what you have learned about inclined planes and wedges, rank the screws in order of hardest to easiest to turn (1=hardest, 3=easiest): A B C Produced and published by the Education Division, The Cleveland Museum of Natural History, 1 Wade Oval Dr., University Circle, Cleveland, OH Last updated 5/4/2016

6 LEVERS A lever is a simple machine that helps you lift or move a heavy object Balance your ruler. Where is the fulcrum? Balance your ruler with the fulcrum at #2. How long is your lever? inches 3. How many weights did it take to balance the ruler? 4. Balance your ruler with the fulcrum at #3. How long is your lever? inches 5. How many weights did it take to balance the ruler? 6. How does making a lever longer affect your ability to do work? GEARS A gear is a type of wheel and axle. The wheels have teeth and move other gears. 1. How many times does gear B turn around when you turn the handle on gear A once? A B 2. How many times does gear C turn around when you turn the handle on gear A once? 3. How many teeth does each gear have? A B C PULLEYS A pulley is a simple machine that helps us do work by changing the direction of the force we use to lift something, and by dividing the weight. 1. How many Newtons of force does it take to lift the weight? N 2. How many Newtons does it take to balance the weight with a one-pulley system? N 4. Using a two-pulley system, how many Newtons does it take to balance the weight? N Produced and published by the Education Division, The Cleveland Museum of Natural History, 1 Wade Oval Drive, University Circle, Cleveland, OH Revised 5/2013.