HOT-AIR BALLOONS

PROBLEM: What keeps a hot-air balloon in the air? How long will the balloon stay in the air?

RESEARCH: Write a one-page paper on hot-air balloons. Be sure to include a bibliography of the book or books you use.

Background: When air or any other gas gets hot and expands, it gets less dense (lighter) because the same amount of air occupies a larger space. Hot-air balloons fly because they contain warmer, lighter air. The air in the balloon, being warm, is less dense (lighter) than the cool air around it. So it floats upward, like cork in water. When the air gets cool, the balloon will sink again.

HYPOTHESIS: What do you think will happen when you put hot air into your balloon?

MATERIALS:

tissue paper

ruler

glue

pen

scissors

plastic ring or cookie cutter

string

hair drier

cardboard

PROCEDURE:

1. Make a cardboard template for the balloon panels from the pattern below. Cut out eight panels from tissue paper.

2. Glue the panel edges together into a balloon shape. You could do this over an inflated rubber balloon.

3. Cut a piece of cardboard for the basket as shown in the pattern. Score each dotted line with a pencil to make it easier to fold.

4. Fold and glue the card into a box shape. Make a small hole in each top corner of the box with a pencil.

5. Thread one piece of thread through each of the holes you just made.

6. Glue each thread on the balloon’s mouth. Allow the glue to dry thoroughly.

7. Hold the top of the balloon and fil it with warm air from a hair drier set on medium. Once the air inside is really warm, let the balloon go and let it rise into the air.

DATA: Take a picture or draw a picture of your balloon. Make a data table that shows how long you held the hair drier up to the balloon and how long it stayed in the air. Vary the amount of time. Use at least three lengths of time and do at least three trials for each time. Bring your balloon to class.

CONCLUSION: This is not optional. You must explain what you learned by doing this activity.

Remember that you must answer the question you asked in your original problem statement.

NOTE: BE SURE TO HAVE YOUR PARENT OR GUARDIAN SIGNS YOUR WORK. PARENTS: YOUR SIGNATURE SHOWS YOUR STUDENT HAS DONE THE WORK.

E-Mail

Judy Schneider

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