Are you up for it?

Inquiry Skills UsedInitiating & Planning: preparing the globes for the eclipse Performing & Recording: recording observations and displaying the eclipse Analyzing and Interpreting: drawing conclusions based on information gathered Communicating: visual, oral, and written communication

Safety Considerations Take precautions when using the hair dryer. Follow electrical safety measures. Do not block the flow of air for the hair dryer. For safety and hygiene reasons, use the balloon pump to inflate the balloon. They can be found in

some dollar stores. Be aware of any latex allergies and adjust your materials accordingly. Be sure that the extension cord has no missing pins (e.g., grounding). When unplugging the hair dryer, pull on the plug not the cord.

BackgroundThe following experiment will give you insight into the role air pressure plays on weather and help explain how airplane wings get ‘lift’. Have you ever put your hand outside the window of a moving vehicle? As you are doing this, hold the palm of your hand flat or parallel to the ground and slowly rotate your hand until it is perpendicular to the ground? Did you notice that with a slight rotation of your hand, as the wind hits your palm, your hand was forced up by the wind? This is what will happen to the balloon as the air from the hair dryer passes over the balloon’s surface. The balloon is hit by the flowing air, which flows around the outside surface of the balloon, pushing the balloon into the centre of the air column created by the hair dryer. The balloon with receive lift until gravity exceeds the force being applied by the air from the hair dryer. As the balloon sits in this stream of air created by the balloon, a low-pressure area is created on the opposite side of the source of the air flow, leaving an ‘empty’ space behind the balloon. It is there because the wind is being blocked by the surface of the balloon. The air rushing over the balloon turns to fill up the low-pressure space, and then tries to keep on going—out the side of the main column. As the jet of air rushes ‘out’ over the surface of the balloon, it is pulled back onto the opposite side of the balloon, keeping the balloon inside the air column generated by the hair dryer.

What You Need Hair dryer (hand-held) Balloon hand pump Access to a wall

Extension Cord Round balloons or Ping pong balls

This activity is suggested for use with the Ontario Curriculum.

Grade 6: Matter and Energy

Contributed by: Roberta Oswald

Air has many properties that can be used for different purposes, including flight.

Flight occurs when the characteristics of structures take advantage of certain properties of air.

What to Do1. Blow up a round balloon and secure it. 2. Turn on the hair dryer and point the airflow straight up. 3. Place the balloon in the flow of air. Observe what happens. 4. Predict what might occur as you experiment with the various strength settings on the hair dryer. Try

to keep your balloon stationary without touching it.

At what angle can you tip the hair dryer without allowing the balloon to fall? Point the dryer straight up again and pass your open hand through the column of air at varying speeds. At what position will your hand disrupt the airflow and the balloon falls?

Move over to a wall. Hold the dryer next to the wall. Point it straight up and put the balloon back in the air. Does it behave differently?If a corner is present, try again in this location and compare.

Team Effort—(2 dryers needed) Toss the balloon up in the air and ‘catch’ it on the rushing air.

Where to Go from Here?Can you feel the ‘sideways air’ when you hold the balloon halfway in the main jet of air? Hang onto the balloon and with your other hand, feel around for the jet coming off the top.

This occurs during a tornado storm. The roof may fly right off buildings as the wind flows over the roof and creates a lower pressure above rather than under the roof, due to turbulence. What other weather phenomena can you explain?

STSE LinksStudents can evaluate the effects of various technologies on energy consumption, and propose ways in which to reduce the amount of jet fuel used by making a more efficient airplane wing design.

Cross Curricular ConnectionsLanguage

Read a book about kite making and create opportunities for text-to-world and text-to-self connections regarding kites.

Read non-fiction books about the invention of a jet plane and write a report about how incorporating components of Bernoulli’s Law has created more efficient and faster fighter jets.

Visual Arts Create a visually attractive and efficient paper airplane design incorporating lessons learned in this

experiment.

Credit Where Credit is DueThis experiment was adapted from ‘Explorabook: A Kid’s Science Museum in a Book’, by John Cassidy; Klutz Press, 1991.