Just how loud does a sound have to be for us to hear it? And how loud is too loud for our ears? Learn to measure levels of sound in this project, and discover the amazing auditory range your ears can detect in the noisy world around you.

Discusses the ear drum receiving vibrations and how the amplitude of those vibrations translates into the loudness of the sound. Good diagrams to illustrate this concept.

Have you ever wondered what it would be like to have an extra sense? What if you could hear above the normal range (ultrasound) like dogs or bats? This project shows you how you can use a camera, tripod and a special filter to take...

This fact sheet on the bobcat provides details on physical characteristics, adaptations, range, habitat, conservation, diet, and other interesting facts. Click the link to hear how a bobcat sounds.