Take-Home Packet to Accompany In-Class Textbook



How do Machines Make Tasks Easier?

Main idea practice

Directions: Fill in the missing words using the Word Bank.

1. ____________________ can be described and measured by ___________________, speed, ___________________and acceleration.

2. __________________ _______ ___ _________describe and explain how objects ___________. Forces, or _______ ______ __________, can change an object’s motion.

3. _____________________ can make work easier by changing the _____________ ____ __________ applied to an object, the ____________________ of the force, or both. The six kinds of simple machines are the lever, ________ _____ _______, pulley, _________, wedge, and screw.

WORD BANK

amount of force

direction

Machines

Motion

move

Newton’s Laws of Motion

position

pushes and pulls

ramp

velocity

wheel and axle

- - - -

Lesson Definitions

Work: Work is the effect of a force applied to an object that makes it move in the direction of the applied force. Pushing on a chair is work because the chair moves in the direction of the force, your push.

Simple Machine: A simple machine is a device that makes doing work easier. The six simple machines are the lever, wheel and axle, pulley, inclined plane, screw, and wedge. They fall into three groups: levers, wheels, and inclined planes.

Mechanical Advantage: Mechanical advantage is the amount by which a machine increases applied force.

Efficiency: Efficiency is the ratio of work done to work put into a machine. The higher the efficiency, the more work the machine can perform. No machine is 100% efficient due to friction.

Effort force: Effort force is the force or energy you apply to the machine.

Output force: Output force is the force or energy the machine uses against the load. Output force must be greater than the resistance (the load) for work to be done.

Technology investigation

Technology investigation title: Compound Machines

Date: _______________________________

Inquiry: What are compound machines made of?

Materials: Popsicle sticks, rubber band, paper cup, tape, toys, instructions including Rules of Safe Use!

Prediction: The Popsicle Stick Catapult will have these simple machines in it: __________ ________________________________________________________________________________________________________________________________________________________________________________________________________________________

Procedure: Examine the toys and decide what simple machines are in each. List them here.

Toy

Simple Machines in toy

Then work with your team to build the Popsicle Stick Catapult (listen to and follow directions). Examine it and list the simple machines seen in it.

Conclusion: All compound machines use ______________ ____________________. The Popsicle Stick Catapult used these simple machines: ______________________________ ________________________________________________________________________________________________________________________________________________

Building a Popsicle Stick Catapult

This catapult project takes about thirty minutes and it uses 13 Popsicle sticks, some masking tape, and a rubber band.

It also shows you fundamental concepts of engineering—the use of simple machines to make compound machines, and the strength of the triangle.

NOTE: The catapult you see in the pictures is larger than the one you are building, but the method is the same.

Here is what you need to make your Catapult:

• 13 Popsicle sticks

• masking tape

• rubber band

• scissors (if you want to cut the tape neatly)

• 3 oz. paper cup, cut down (for holding the load)

Here is the basic process for taping sticks together. You lay out your tape with the sticky side up then place two sticks end to end right on it. Press the sticks down firmly on the tape. Do at least two full revolutions of the tape. Add a third stick to the end of the first two. Fold the two loose stick ends to meet, and tape them. This is your first triangle. Make three of these triangles.

Hold two of the triangles together side by side and tape them only on one side. This forms a hinge, keeping them attached while allowing them to open up. The arrow shows the side taped together. Our pyramid is going to take shape.

Lay one triangle down on the table and split the legs on the two you taped together. Slide them right over the one on the table. Tape everything together.

Your completed pyramid shape should look like this.

Now let's build the arm of the catapult. We use three Popsicle sticks. Put two sticks end to end then put one stick right on top of them.

Use a loop of masking tape to put the cup on the catapult arm, about 2 cm from the end so you have room for your thumb to pull the catapult down.

Now wrap one end of the rubber band around the catapult arm just under the cup and tape it firmly in place.

Using a couple of pieces of tape, connect the other end of the catapult arm to the place where the three triangles meet. This is really tricky to do ! Try, try, try! Do your best and secure the catapult arm firmly. But it has to move freely. Think of the tape as being a kind of a hinge.

The only thing left to do now is to watch Mr. McKinsey show you how to wrap the other end of the rubber band around another stick and place it at the top of the catapult.

RULES OF SAFE USE:

1. You may only use small, dry, paper balls (or ping pong balls) in your catapult.

2. Do not direct your catapult at people.

3. Your catapult does not leave the Science lab until Mr. McKinsey instructs.

4. Any catapult left after departure date will be thrown out.

word cross

Word Search

How did the scientists get to their vacation destination?

|T |H |E |

|LEVER |MECHANICAL ADVANTAGE |OUTPUT FORCE |

|PULLEY |SCREW |SIMPLE MACHINE |

|WEDGE |WHEEL AND AXLE |WORK |

__ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __

Bill Nye Simple Machines Viewing Guide

1. Simple machines let us change the ___________ and direction of ______________.

2. When Bill pulled down on the rope running to the pulley, which direction did the Crate of Science go? __________________________

3. What type of simple machine was Bill’s bottle-launching catapult? ______________

4. The part of a lever around which it pivots is called the _______________

5. When the kids pushed down on the spoon bowl, which direction did the ping pong ball go? _________________________

6. Bill demonstrated that a bunch of levers pivoting around one fulcrum is a ___________ and _____________.

7. Gears are wheels with ___________.

8. A ___________________ is a modified ramp, or ________________ _________.that allows you to easily achieve height, but you must walk a longer distance.

9. Why didn’t the string break when the boy pulled the book up the ramp? ________________________________________________________________

10. A spiral staircase is a lot like a ___________.

11. A screw is a _____________ wrapped around a rod.

12. The distance between the threads on a screw is called the ___________.

13. A prosthesis is an ______________________ ____________.

14. A crane uses ___________ to lift heavy loads.

15. With a pulley system, as in the tree fort the children were building, you use more rope (distance) but less ___________ to lift a load.

16. A sailboat uses _______________ to raise the sails.

17. Who won the Tour de Science ’93? _________________________

18. Name two compound machines (complex machines made up of more than one simple machine) appearing in the music video. __________________________

Lifting, lifting lAB

DATE: ________________________________

INQUIRY: How do pulleys and pulley systems change the direction of a force, the amount of force, or both?

MATERIALS: Fixed pulleys, movable pulleys, and various pulley systems; spring scales; masses.

PROCEDURE: Following Mr. McKinsey’s instructions, you and your team will move from station to station investigating the force necessary to move a given mass using the three types of pulleys and various pulley systems. You will record data and develop a hypothesis about the mechanical advantage of each pulley and pulley system.

(pictured left to right: 5-pulley system; movable pulley; fixed pulley)

PREDICTION: The pulley or pulley system providing the greatest mechanical advantage will be _________________________________________. The pulley(s) or pulley system(s) that changes the direction of the applied force will be ____________________________________ ______________________________________________________The pulley or pulley system that does not provide any mechanical advantage will be _________________________.

DATA: ________________________________________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________________

CONCLUSION: ________________________________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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Lesson Review

1. Main Idea. Explain how simple machines can make tasks easier. __________________ _______________________________________________________________________________________________________________________________________________________________________________________________________________

2. Vocabulary. Why is the efficiency of a machine always less than 100%?___________ ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

3. Reading Skill: Cause and Effect. How does a large steering wheel make it easier to turn a school bus? _________________________________________________ ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

4. Critical Thinking: Apply. Piano moves sometimes move pianos up stairs, into trucks, and even through windows of tall buildings. Describe how simple machines can help them. Give at least three examples. ___________________________________________ _________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Test Prep. Mechanical advantage is…

a) …the amount by which a machine multiplies force.

b) …the amount of force applied to a machine.

c) …the complexity of a machine.

d) …the amount of resistance force working against a machine.

First, Second and Third Class Levers

|[pic] |[pic] |[pic] |

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First Class Levers:

The first class lever uses a fulcrum in between load and effort, and the applied force and load are at opposite ends. The diagram above shows a first class lever set up to move a heavy load with a small applied force. The force must be applied over a long distance, in order to make the heavy load move just a small amount. By adjusting how far the fulcrum is from the load, you can control the mechanical advantage. The closer it is to the load, the more force is applied.

Second Class Levers:

The second class lever is one where the fulcrum is at one end, and the applied force at the other. The load that is to be moved is between them. This lever causes the load to move in the same direction as the force you apply. Just as with a first class lever, how close the load is to the fulcrum determines by how much your force will be multiplied. If you want to move a very large load with a small applied force, you must put the load very close to the fulcrum.

Third Class Levers:

The third class lever has the fulcrum at one end of the lever, but this time the load is at the other end, and you apply a force in between. This lever cannot give any mechanical advantage. Regardless of where you apply the force, the force you apply must always be greater than the force of a load. If you were using this lever to lift an object at a distance, it would require less force to just stand above it and lift it up. Using the lever will require more force! So why use a third class lever? Because the load moves in the same direction as the force you apply; it’s convenient.

What is mechanical advantage?

When a machine takes a small input force and increases the magnitude of the output force, a mechanical advantage has been produced.  

Information retrieved from for educational use.

Lesson Three Vocabulary

work ___________________________________________________________________ __________________________________________________________________

simple machine ____________________________________________________________ __________________________________________________________________

mechanical advantage _______________________________________________________ __________________________________________________________________

efficiency ________________________________________________________________ __________________________________________________________________

effort force_______________________________________________________________ __________________________________________________________________

output force ________________________________________________________________________ ______________________________________________________________________________

The Six Simple Machines:

Lever

Inclined Plane

Wheel and Axle

Screw

Pulley

Wedge

Supporting the main Idea

What to Do: Find details in the reading that support the lesson’s Main Idea. Rewrite the details in your own words (do NOT copy from the book) on the lines below, and write the page number where you found the detail. One has been done for you as an example.

This Lesson’s Main Idea is, Machines can make work easier by changing the amount of force applied to an object, the direction of the force, or both. The six kinds of simple machines are the lever, wheel and axle, pulley, ramp, wedge, and screw.

1. Mechanical advantage in a machine means it multiplies your effort force to make a greater output force on the load, making work easier. Page F123

2. _______________________________________________________________________________________________________________________________________________________________________________________________________________

3. _______________________________________________________________________________________________________________________________________________________________________________________________________________

4. _______________________________________________________________________________________________________________________________________________________________________________________________________________

5. _______________________________________________________________________________________________________________________________________________________________________________________________________________

6. ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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Homeroom ____________________________________________

Student Name __________________________________________

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main ideas of Ch. 19 Lesson three

Machines can make work easier by changing the amount of force applied to an object, the direction of the force, or both. The six kinds of simple machines are the lever, wheel and axle, pulley, ramp, wedge, and screw.

Adapted for limited educational use from

Down

1. This is the amount by which a machine increases applied force.

5. Many levers in a circle make this simple machine.

6. You apply this energy to the machine.

10. This is the effect of a force applied to an object that makes it move in the direction of the applied force.

Across

2. If it has an arm moving around a pivot point, it's this type of simple machine.

3. This device makes doing work easier.

4. This is the ratio of work done to work put into a machine.

5. Take two inclined planes, put them together, and you have this simple machine.

7. It's a ramp.

8. This energy is what a machine uses against a load.

9. Wrap an inclined plane around a shaft for this simple machine.

11. Need a lift? Use this simple machine.

This Lesson’s Main Idea is ______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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