This document provides instructions for an activity that teaches about forces through experimentation with a homemade bucket. Students will create a mini bucket with string and a paper cup, then place various objects inside and spin it around their head. By observing how each object reacts, students learn that centrifugal force pushes objects outward and is the force that keeps riders from falling off amusement park rides. The activity allows students to observe that some features of an experiment can stay the same while others change.

1. By: Emily Williams Spring 2010 Fun With Forces!

2. Standard 4.6: Common Themes Indicator 4.6.4: Observe and describe that some features of things may stay the same even when other features change (Core Standard). Taken from: http://dc.doe.in.gov/Standards/AcademicStandards/StandardSearch.aspx Link to activity: http://www.eurekalert.org/kids/aaas/Fun_with_Forces_final.pdf

3. Definitions: Force: An influence on a body or system, producing or tending to produce a change in movement or in shape or other effects. Gravity: The force of attraction by which terrestrial bodies tend to fall toward the center of the earth. Motion: The action or process of moving or of changing place or position; movement. Centrifugal Force: A force that tends to move objects away from the center in a system undergoing circular motion. Taken from:http://dictionary.reference.com/

4. Background Information: Sir Isaac Newton, a scientist who lived 300 years ago, said “a body in motion will move in a straight line unless acted upon by an outside force.” Motion is one of the key topics in physics. Everything in the universe moves. It might only be a small amount of movement and very slow, but movement does happen. Don't forget that even if you appear to be standing still, the Earth is moving around the Sun, and the Sun is moving around our galaxy. The movement never stops. Over the years, scientists have discovered several rules or laws that explain motion and the causes of changes in motion. The physics of motion is all about forces. Forces need to act upon an object to get it moving, or to change its motion. Changes in motion won't just happen on their own. Taken from: http://www.physics4kids.com/files/motion_intro.html

5. Materials You will need to gather the following materials before starting the project: String A paper cup Pen Penny Water Scissors Ruler Tape Journal Gripper Eraser Notecard All of the materials needed for this project can be found in the science kit provided by your teacher!

6. Things to Think About Before Starting the Project Picture yourself at an amusement park. Imagine some of the rides that you love to go on like roller coasters and scramblers. These rides move in circles and have steep curves. Rides like these make you feel like you’re being pushed outward. Before you begin this experiment, please answer the following question with a personal prediction in the journal provided: What do you think is the “outside force” that stops you from not only falling out of the roller coaster when it goes upside down, but also keeps you from shooting into the sky when you go over huge hills? This question will be answered after you have finished the experiment!

7. Project In this project you will test “the force” with your own mini-bucket. You will create your bucket with the materials provided, and then use your bucket to observe the force exerted on many different objects. After each object you test you will observe the changes in the experiment and record your observations in the journal provided.

8. Procedure Make your own mini-bucket. With the pen, poke a hole near the rim of the cup. Poke another hole directly across from the first hole, on the other side of the cup. Cut two pieces of string about 2 feet long each. Attach each string to a side of the cup by looping it through the hole, tying a knot, and taping it. Place one of the objects inside the cup. Take the ends of the string, and whip the bucket around in a circle over your head. Be sure to stand far away from your friends and other objects. You may have to sway the bucket back and forth before you can make a full circle.

9. Procedure Continued Once you have tested the first object, continue testing the rest of the objects in the box. To keep track of your observations, create a table like the one below in the journal listing each object and the outcome of the experiment for that specific object. What would happen if you shortened the strings of your bucket? Would it have any effect on the object? Does it matter how fast you whip the bucket over your head?

10. Procedure Continued The water should be your last object that you use in the experiment. Once you have completed it, go back and look at your table and each of the objects you tested and their outcomes in the experiment. Did the experiment change with any of the objects you tested? Why or why not? The last question you should answer is the question from the beginning of the project: What do you think is the “outside force” that stops you from not only falling out of the roller coaster when it goes upside down, but also keeps you from shooting into the sky when you go over huge hills?

11. Summary By doing this project you should have a greater understanding of the way force acts against objects in an experiment. You should also be able to observe and describe that while you are doing an experiment, some features of things may stay the same even when other features change. You should be able to describe the way centrifugal force works to help you not fall out of amusement park rides. You can respond to this project online by going to my pbworks website at http://eawilliams.pbworks.com/ and leaving a comment! 

12. Resources Definitions: http://dictionary.reference.com/ Background Information: http://www.physics4kids.com/files/motion_intro.html Original Project: http://www.eurekalert.org/kids/aaas/Fun_with_Forces_final.pdf Image: http://sciencefair.math.iit.edu/projects/forces/roller_coaster.jpg