Polymer Bouncing Balls

What is a polymer?

Polymer

• A large molecule that is made up of repeating subunits connected to each other by chemical bonds.

• Examples: – Turtle Shell

– Anything Plastic

– Proteins- Hair, Nails

– Silly Putty

– Rubber

Not a polymer • Elements – Periodic Table

• Metals- Gold

• Salt

Focus How does the height from which you drop a ball affect the height that it will bounce?

HYPOTHESIS: I think if a ball is dropped from a greater height then, ______________________________________________________________________________________________________________________________

I think this because _____________________________________

______________________________________________________________________________________________________________________________

Experiment Plan/Procedure • INDEPENDENT VARIABLE – (the variable you are changing)

• DEPENDENT VARIABLE –(the measurement variable)

• CONSTANTS –(the variables you will keep the

same)

Independent Variable

• this is the variable that is purposely changed in an experiment. You change this variable to see if it makes a difference. A well designed experiment will have only one independent variable.

Dependent Variable

• this is what will be observed and measured in the experiment. This is called your measurement variable that tells/measures the difference the independent variable makes. This responding variable responds to the change you made in the independent variable.

Constants

• these are the variables that remain constant throughout the entire experiment in order for a valid test to occur.

MAKE One BOUNCY BALL • Materials

• ½ c. water

• ½ t. borax (a laundry booster; can be found at Walmart and most grocery stores)

• 2 T. school glue

• food coloring

• cup

• spoon

• paper towels

What does your experiment look like? INDEPENDENT VARIABLE (the variable you are changing) ________ DEPENDENT VARIABLE (the measurement variable) _______________ CONSTANTS (the variables you will keep the same) _________________________________

Recipe 1.Stir the water and borax in a cup until the borax is dissolved. 2. Mix coloring into your glue. (Tip: Making two or more colors of glue will make a very colorful bouncy ball!)

3. Drop your glue by the tablespoon into the borax solution, stirring the glue as it is pouring in. As the glue hits the solution, it will solidify into a slimy substance.

4.Now have fish out the glue with your hands. If the glue is still sticky, dip it into the borax solution over and over until it’s all solid.

5.The more you handle the slime, the firmer it will become. Eventually, you will be able to form it into a ball that bounces!

Procedure 1.Gather your materials.

2.In groups of 4, divide the activities so that one student drops the ball, one student watches the bounce and estimates the height to which it bounces, one student measures the height of the bounce, and one student records the data.

3.Determine the height of the drop and the bounce by measuring from the bottom of the ball.

Procedure 4. Drop a ball from 50 cm and record how high it bounces. The height to which the ball bounces is to be estimated as carefully as possible.

5.Repeat steps 3 and 4 but change the drop height to 1OOcm, 10 cm and 200 cm

6.Repeat steps 3-5 two more times so you have three trials of data collected.

7. Find the mean (average) of the three trials and use the mean to graph.

8. Clean up your work station and replace your supplies.

Collecting Data

• Complete Chart

• Complete Graph

Questions 1.How did you use scientific knowledge to create your structure?

2.How did your thinking and/or approach change throughout the task?

3.From the activity, what skills do you believe are important for scientific collaboration?

4.What challenges would scientist face when developing their own projects?

5.How do you believe scientist overcome these challenges ?