Alley Mill Closed for Renovations
The Alley Mill will be undergoing renovations much of summer of 2014. It will be open on weekends ONLY in July. There will be fencing around the Mill which will prevent close access. We are working to protect and preserve the Mill for the future. More »
OBJECTIVES: The students will be able to describe what sound waves are and how a bat uses them to catch insects.
MATERIALS: Tape player, tape of soft music or other sounds, glass pie pan or clear container, water, eye dropper, over head projector.
1. Have students close their eyes. Play a tape of soft music or other subtle sounds. Have the children cup their hands behind their ears as they listen. Ask "Does cupping your ears help you hear the music better? How are your cupped hands like a bat's ears? Why do you think bats have such big ears?"
2. Fill the pan with about one inch of water. Place on the overhead projector. Turn the projector on and let the water settle. When the water is calm, drop a couple drops of water into it from the eye dropper.
3. What happened? Could you see the ripples move out from the source? What happened when the water waves reached the edges of the pan? Compare water waves to sound waves from a bat.
Courtesy Carlsbad National Park
Did You Know?
Big Spring, at Ozark National Scenic Riverways in Missouri has a daily flow of 286 million gallons of water. This is enough to fill a typical pro football stadium once a day. More at www.nps.gov/ozar More...