Objectives

2. AIM: What is an Echo? Objectives Define the term “echo”. Identify animals that naturally use echolocation Describe echolocation

3. AIM: What is an Echo? Vocabulary Echo, sonar, echolocation, sonogram

4. What do we Know? What happens when a wave hits a barrier? It is either absorbed, or it bounces back. What is it called when it bounces back? A reflection An echo, is a reflection of a sound wave

5. What do we Know? DEFINITON: An echo, is a reflection of a sound wave

6. What is Echolocation?

7. What is It? What is echolocation? Certain animals, like bats, use echolocation to find their way around, as well as for finding food.

8. How does a bat figure out where he is going?

9. Certain animal give off high pitched sound. These sounds are reflected off of objects. These animals are able to locate themselves and their prey because they have developed a sophisticated internal process for deciphering the returning sound (wave) echoes.

10. Did you Know? As major predators of insects, bats are beneficial and essential to the balance of nature. A common brown bat can devour 600 mosquitoes in one hour!

11. Pop Quiz Answer True or False to the following Questions

12. HOW MUCH DO YOU KNOW? How often have you heard someone say, "I'm as blind as a bat!" Bats are the subject of many popular misconceptions. No matter how much bats are liked (or disliked), they are under-appreciated.

13. How much do you know about bats? • Are bats blind. 2. Are bats rodents. 3. Bats are the only flying mammal. • 4. Is the bas a threatened species?. • 5. Are bat droppings used to make some antibiotics. • 6. Bats cause a high percentage of rabies cases.

14. Answers: 1. False; many bats have good vision; they are active at night and have developed a keen sense of sound 2. False; bats belong to the order Chiroptera; 3. True bats are the only flying mammal 4. True; over 50% of American bat species are in severe decline or endangered. 5. True, bat droppings are used in medicines 6. False; most of the fatal cases of rabies in the U.S. are caused by rabid dogs;

15. What other animal use echolocation? Bats, dolphins, certain whales, some birds.

18. Dolphins us Echolocation by the emission of sound from their head region. The received echoes pass through special sound conducting tissue in the lower jawbone to the inner ear.

19. How sensitive is echolocation? • Echolocation is extremely sensitive. • For example, dolphins in aquariums can distinguish between objects that are the size of a kernel of corn at about 50 feet (15.2 meters) away.

20. Do people use echolocation?

21. What is It? We use a form of echolocation Called SONAR: SONAR is used to map the ocean floor, SONAR helps locate underwater objects, SONAR is used in weather forecasting.

22. Why does the navy use Echoes? It is called SONAR

23. What does Sonar mean? Sound Navigation and Ranging

24. How is the echo use in this picture?

25. With SONAR, we have mapped the ocean floor!

27. With Sonar The ship has a transmitter which send out sound waves The sound waves reflect off of an underwater object, producing an echo The sound waves bounce back from the reflection. The ship also has a receiver which picks up and then interprets the echo to pinpoint exact locations.

28. Outgoing Sound

29. Reflected Sound

30. What is this Navy Ship trying to do ?

31. Ultrasound vs. Infrasound?

32. Ultrasound = sound higher then we can hear • like a dog whistle • like the sonar used by animals and submarines • echolocation

34. Infrasound = sound lower then what we can hear • Elephant stomp

35. Where do we use ultrasound?

36. By Doctors: • Expectant mothers get ultrasound tests to examine their unborn babies for health problems • A viewable picture is actually developed. • Why do you think the ultrasound is preferred over the older x-ray technology on expectant mother?

37. By People: • Used a lot in teeth cleaning

38. AIM:What is an echo? Class Activity: W/S Concepts 8-4

39. AIM:What is an echo? Homework: INTERNET QUESTIONS