LEVER S LEVERAGE. Brenton Dunn. Dara Dispanurat. How does the position of the weight affect the balancing point of the lever? Ms.

Transcription

1 LEVER S LEVERAGE How does the position of the weight affect the balancing point of the lever? Brenton Dunn Dara Dispanurat Ms. Guan, Period 3

2 ABSTRACT Have you ever wondered what would happen if we imbalanced two objects of unequal weight? Well, that s exactly what information is being balanced in this paper. From balancing simple household objects like a plastic sand bucket and a water bottle on a yardstick to identifying the fulcrum, effort, and load on objects that were never thought of as levers, you will explore the constant machines (that might not even be moving) in our modern world. In the following, we will explore and learn about: Problem: Having two various objects of unequal weight is unbalanced on a lever. How can we fix this so that both objects will be balanced? Hypothesis: If the placement of objects varies on a lever, whether nearer or farther from a fulcrum, then their balance will vary. Procedure: We created our lever, using tape, a yardstick, and a 7 oz and 4 oz object. Then, we conducted our experiment, recording our information using math, video, and pictures. See page 5 for full details. Variables: We manipulated the distance from the fulcrum, for the heavy object. We kept our water bottle stationed at one place. Results: After testing our lever, we found that our hypothesis was correct, after the lever finally balanced out after slow movement of the heavy object towards the fulcrum in the middle on the lever. Conclusion: Like the results, our project results reflected that our hypothesis was correct and the two objects did eventually balance out. 1

3 TABLE OF CONTENTS 1. INTRODUCTION 3 2. HYPOTHESIS / STATEMENT OF PROBLEM MATERIALS PROCEDURE DATA / RESULTS EXPLANATION / SCIENCE.8 7. CONCLUSION GLOSSARY ACKNOWLEDGEMENTS WORK LOG BIBLIOGRAPHY 13 2

4 INTRODUCTION You re sitting alone at the park. The sun is setting, and you stand up to head back to your house before it s too late and have to face your angry mother. You pass by the seesaw, and stare at it as a small bird flies and perches on it, happily chirping. A crow flies by and perches on the other side of the seesaw. It tilts a little bit, the crow s side leaning towards the floor. It caws in fright and flaps away. The seesaw jerks back into its original position, the little bird also frightened, and flies away quickly. You wonder how the simple lever really works. Later that night, after gathering some materials from your garage, you can finally piece together a handmade seesaw that you and observed earlier that day. You sit down, right in front of your model. Time to experiment. 3

5 HYPOTHESIS How does the position of the weight affect the balancing point of the lever? If the placement of objects varies on a lever, whether nearer or farther from a fulcrum, then their balance will vary. We believe that if we place two objects, one object heavier than the other, and consistently but slowly, move the heavier object closer towards the fulcrum, then the resistance force will lessen and eventually the two objects will balance out. For example: Using a bucket weighing 7 oz Using a water bottle weighing 4oz The bucket, naturally weighs more If placing the bucket near the fulcrum, then it will eventually balance out with the lighter water bottle on the other side of the lever. WHY DO WE BELIEVE THIS? We chose this hypothesis because we already know that if two objects are placed at equal sides of a first class lever, then the heavier object would obviously tilt towards the ground. However, we think that if moving the heavy object towards the fulcrum, which is a middle point, then the heavy object will balance the lighter one out. 4

6 VARIABLES What is a manipulated variable? A manipulated variable is also known as an experimental variable. It is the variable that you change during your experiment, or the variable that is used for other materials to experiment. What was our manipulated variable? Our manipulated variable was the distance from the fulcrum. We constantly would move the bucket (which was the heavier object) closer and closer to the fulcrum until it would finally balance out on the lever. What is an independent variable? An independent variable is a variable that is non - experimental. It is the variable that stands on its own. According to Google, It does not depend on that of another (variable). Basically, it s the variable that is literally independent. What was our independent variable? Our independent variable was the bucket and water bottle itself. Both of these objects were indeed of varied weight, but they were on their own and did not change at any point of time during our experiment. What are controlled variables? Controlled variables are variables that must remain the same during the experiment in order for it to be fair and orderly. What were our controlled variables? Our controlled variables were the same yardstick, same weight of object on the opposing side, same location, and same weather (wind could have affected the placement and balance of the objects, which only weighed a few ounces) 5

7 MATERIALS - HOW TO CREATE YOUR LEVER To Create Your First Class Lever Out of Household Items: 1. A Yardstick - This will be your lever 2. A Tape Roll - This will be your fulcrum 3. A Plastic Kid s Bucket (anything weighing 7 oz) - This will be your resistance force 4. A Mini Kirkland Bottle (anything weighing 4 oz) - This will be your load (For the extra materials seen in our video) 1. For a second class lever: A can opener (see load, fulcrum, and force points below) 2. For a third class lever: A Tennis racket (see load, fulcrum, and force points below) (You can also use other materials, as long as they have the same points as the materials we had used in our experiment) 6

8 PROCEDURE 1. First, set up your lever. Gather your materials, which would include a large sized roll of tape, a yardstick (those from Home Depot work perfectly), and two objects weighing 7 oz and 4 oz. 2. Tape your yardstick and tape roll together at the middle point of the yardstick, which will be the fulcrum. (you can use the tape from the tape roll to do this) 3. Carefully place the 4 oz and 7 oz objects at opposing sides of the lever. Make sure that they are first at equal distances from the fulcrum. 4. Now, we can begin the experiment. Carefully move the 7 oz object closer to the fulcrum at a desired distance and pace (there isn t any required pace, and it might take a while and multiple tries to balance the two). 5. Once the two objects are balanced, (make sure to have lots of patience!) record your data and measure the distance that the 7 oz object was from the fulcrum. 6. Transfer your data onto any other forms of media (pictures, videos, etc) You have successfully completed your experiment! 7

9 RESULTS After moving the heavier object weighing 7 oz closer and closer to the fulcrum, it eventually balanced out with a 7.5 inch difference. Therefore, our experiment did prove to be successful. Our hypothesis was correct, and the statement of problem was fixed. We took a picture of our final balance of the lever, which had the weights of the objects, and the distances from the fulcrum. See below for the picture. 8

10 SCIENCE BEHIND THE EXPERIMENT The lever balanced when the lighter weight (4oz) was a little less than twice distance away from the fulcrum as the heavier weight (7oz). Using the equation M 1 a = M 2 b, we could figure out the lengths of the two items away from the fulcrum. The heavier object (7oz), was 10 inches away from the fulcrum. The lighter object (4oz), was 17.5 inches away from from the fulcrum. After I plugged the numbers into the equation, it worked. (4)(17.5) = (7)(10) 9

11 CONCLUSION After testing our lever, we found that our hypothesis was CORRECT! Here was our hypothesis: If the placement of objects varies on a lever, whether nearer or farther from a fulcrum, then their balance will vary. Based solely upon the data and results that we had collected, our hypothesis was correct. If the placement of objects varies on a lever, whether nearer or farther from a fulcrum, then their balance will (and it did) vary. After balancing our two objects on the lever, the heavier object weighing 7 oz balanced out with the lighter 4 oz object. This was due to the movement of the heavy object, getting closer to the fulcrum on a 36 - inch lever. After several attempts of moving our manipulated variable and testing its balance, we finally got the results and balance we needed on the lever and could therefore use its data to test in the equation used (M 1 a = M 2 b). 10

12 GLOSSARY Lever: (n) a rigid bar resting on a pivot, used to help move a heavy or firmly fixed load with one end when pressure is applied to the other. Fulcrum: (n) the point on which a lever rests or is supported and on which it pivots. First Class Lever: (n) a class of lever in which the fulcrum in the middle: the effort is applied on one side of the fulcrum and the resistance (or load) on the other side, Manipulated Variable: (n) the variable in an experiment in which it is the experimental variable, or the variable that is changed. Independent Variable: (n) the variable in an experiment that undergoes no change; or the variable that stands alone. Controlled Variable: (n) the variable(s) in an experiment that must remain the same or under certain conditions so that the experiment is fair. Resistance Force: (n) the force which an effort (of a person or object) must overcome in order to do work on an object via a simple machine. Resistance force, like most other forces, is measured in newtons or in pounds-force. Load: (n) a weight or source of pressure borne by someone or something. 11

13 ACKNOLEDGEMENTS We would like to thank Brenton s parents for allowing us to conduct, shoot, and film our experiment. We would also like to thank Mr. Choi for inspiring us to conduct this experiment. We would also like to thank Dara s parents for buying the materials for the experiment. Thank you all. 12

14 WORK LOG DATE (DAY MONTH YEAR) PERSON (BRENTON/DARA) TIME (HOURS MINUTES) WHAT YOU DID 2 MARCH 2017 BRENTON 2HR RESEARCH WHAT TOPIC TO PICK 3 MARCH 2017 DARA 30 MIN BOUGHT AND GATHERED MATERIALS 5 MARCH 2017 DARA 45 MIN RESEARCH NOTES 5 MARCH 2017 BRENTON 1HR 30 MIN RESEARCH NOTES 6 MARCH 2017 BRENTON 50 MIN RESEARCH PAPER 8 MARCH 2017 DARA 30 MIN PREPARED MATERIALS 9 MARCH 2017 BRENTON 2HR 45 MIN CONDUCTED EXPERIMENT AND SHOT VIDEO 9 MARCH 2017 DARA 2 HR 45 MIN CONDUCTED EXPERIMENT AND SHOT VIDEO 10 MARCH 2017 BRENTON 50MIN RESEARCH PAPER 11 MARCH 2017 DARA 30 MIN EDITED VIDEO 11 MARCH 2017 DARA 40 MIN ORGANIZED PAPER, RESEARCH NOTES, AND GATHERED INFO 13 MARCH 2017 BRENTON 50MIN RESEARCH PAPER 14 MARCH 2017 DARA 40 MIN RESEARCH PAPER 14 MARCH 207 BRENTON 2HR EDITED VIDEO 14 MARCH 2017 BRENTON 1HR 30 MIN RESEARCH PAPER 13

15 Bibliography Alexandra. Lever of Human Body. THE PHYSICS CORNER, WordPress.com. Availabe from internet; accessed 10 MARCH 2017 Behnke, Robert. Levers work to create movement in the human body. HUMAN KINETICS, Human Kinetics. Available from te-movement-in-the-human-body, interent; accessed 10 MARCH 2017 Carr, K.E. Levers - Simple Machines. QUATR.US, Quatr.us. Available from internet; accessed 10 MARCH 2017 Kurtis, Ron. Levers are Simple Machines. School for Champions, School for Champions. Available from nyvb0, internet; accessed 3 MARCH, 2017 Lever. Wikipedia, Wikimedia Foundation, Inc. Available from internet; accessed 5 MARCH 2017 Levers. Home Science Tools, Home Training Tools, Ltd. available from. -teaching-tip, internet; accessed 5 MARCH 2017 Lever Action. All Science Fair Projects, Utah State Office of Education. Available from /abb50fdcef3b82d048a551c64af64ffc.html, internet; accessed 2 MARCH 2017 Levers and Force. Science Fair Adventure. ScienceFairAdventure, Available from 14

16 5, internet; accessed 2 MARCH 2017 Lever systems in the human body. YouTube. Human Anatomy Education, 28 SEPTEMBER Available from internet; accessed 10 MARCH 2017 Science Buddies Staff. "Give It a Lift with a Lever." Science Buddies, Science Buddies. Available from ys_p065.shtml, internet; accessed 2 MARCH 2017 The mighty mathematics of the lever - Andy Peterson and Zack Patterson. YouTube. TED-Ed, 18, NOVEMBER Available from internet; accessed 5 MARCH 2017 What is a Lever? Teacher s Activity Guide, Scholastic. Available from internet; accessed 5 MARCH 2017 Zechman, Megan. Science Activities to Learn About Levers. EducationPossible, Education Possible. Available from internet; accessed 2 MARCH 2017 Zimmerman Jones, Andrew. How a Lever Works. ThoughtCo., ThoughtCo. Available from internet; accessed 4 MARCH