DO YOU HAVE A QUESTION?

• Question 1: How can you find the balance point of any shape of paper without trying to balance it?
• Question 2: Is a shape's balance point the same as its center of gravity?
• Question 3: If I have more questions on balance or motion, is there a person I can call?

Question 1: How can you find the balance point of any shape of paper without trying to balance it?

Challenge your students to research this or test their own ideas. Later, introduce this activity. This activity will show students how to use tools to find the balance point of any strange shaped piece of paper.

Supplies:

• Tagboard, one per student
• Scissors
• Bulletin board
• Pushpins
• String
• Hole puncher
• Washer or some kind of weight to tie to the end of a piece of string.
• Marker

Activity:

1. Pass out a sheet of tagboard, 8" string, 1 weight, 1 pushpin and colored chalk to each student.
2. Have students cut a triangular shaped piece from the tagboard.
3. Punch a hole in each corner of the tagboard.
4. Tie a weight to the end of a piece of string about 8" long and a loop on the other end. (You will probably need to show them how to make the loop.)
5. Use a pushpin to let the triangle swing freely by one of its holes. Do this part against the bulletin board.
6. Remove the pushpin, and now hang the string by its loop to the pushpin and then hang the triangle. Let the triangle swing freely until it stops.
7. Draw the line of the string across the face of the triangle.
8. Do the same thing with the other two holes.
9. In the end, you will have draw three lines which cross at the same point (hopefully).
10. This is the center of balance!
11. Test it out by balancing it on your finger!
12. You can test out any shaped piece of tagboard by doing the same steps as the triangle. This time, punch three holes that they are somewhat equally spaced from each other (just an approximate). Hang the string and the shape on the pushpin. Draw the line. Move the string to the second and third holes drawing the lines each time. You should have a point where the three lines intersect, this is the balance point. Once again, test it out!

Question 2: Is a shape's balance point the same as its center of gravity?

Answer: Yes, if the object is on the surface of the earth, the balance point and the center of gravity are the same point.

Question 3: If I have more questions on balance or motion, is there a person I can call?

Answer: A great resource for puzzling student questions is MAST, the Math and Science Teachers' Hotline, located at the University of Northern Colorado. Their phone number is 1-800-866-MAST (6278).

Any Great Ideas?

 Hands-On-Science Menu School District 11 Top of Page