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Science Corner: July 2013 Archives

Why do you need additional flour and water when you bake an Angel Food Cake at high altitude?

A cake's rising depends on steam and bubbles rising, and both are affected at high altitudes. The bubbles form much bigger, so you need the flour to create a stronger structure to hold them. The water in the cake will boil much faster, so you need to add more to keep the cake from drying out.

How does a siphon work? And what is the role of air pressure in a siphon?

The tube in a siphon has to be filled with a liquid and the outside tube has to be longer than the container. Also, the liquid has to be cohesive so the molecules will pull the others along. Atmospheric pressure does not play a role.

Using sound to lift objects

Science Commentator Bob Fournier tells us about recent discoveries in the field of acoustic levitation.

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