How to crush a soda can using the power of air. Continue reading
Fascinate your students with this large scale re-enactment of Isaac Newton’s classic thought experiment.
This is a very practical informal resource video for elementary science teachers based on the Ontario science curriculum unit about flight – Grade 6
This demo illustrates the presence of atmospheric air pressure and shows how the force that it exerts is greater than the force of gravity in some situations. Continue reading
On this episode of The Spangler Effect, fire, ice and a steel drum are all Steve needs for his final experiment. But don’t worry… you’ll learn how to perform the classic Can Crusher trick using an ordinary soda can and a little atmospheric pressure. Get a behind the scenes look at what happens as Steve and his team prepare for his next appearance on the Ellen DeGeneres Show.
The Spangler Effect
The 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.
Air takes up space, has weight, and has pressure. These properties of air create forces that affect structures and can create natural phenomena that affect our way of life and have effects on our weather. The following experiment may give you some insight into the role air pressure plays on structures and the weather around us. Air pressure can be explained by Pascal’s law that says that the force of air acts the same in all directions. We don’t normally feel air pressure because the air pressure is evenly distributed all over and against our skin.
Helicopters have propellers that let them move sideways, and up and down. They are able to hover, which means they can stay in the air even though they are not moving. In this activity, students can see the movement of a miniature helicopter, and compare it to seeds or leaves traveling in the air. Helicopters are affected by weight, shape, and surface area. Weight, lift, thrust, and drag are the most important factors in flight and should be discussed as part of this activity. Making helicopters helps us to compare and contrast various characteristics of flight.
In this activity, students construct a paper “copter” and investigate some of the factors that determine how the copter works. Click the following link for the complete worksheet.