Define the term “echo”.

Identify animals that naturally use echolocation

Describe echolocation

AIM: What is an Echo?

Echo, sonar, echolocation, sonogram

AIM: What is an Echo?

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

DEFINITON:

An echo, is a reflection of a sound wave

What is echolocation?

Certain animals, like bats, use echolocation to find their way around, as well as for finding food.

How does a bat figure out where he is going?

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.

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!

Answer True or False to the following Questions

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.

How much do you know about bats?

1. 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.

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;

What other animal use echolocation?

Bats, dolphins, certain whales, some birds.

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.

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.

Do people use echolocation?

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.

Why does the navy use Echoes?

It is called SONAR

How is the echo use in this picture?

With SONAR, we have mapped the ocean floor!

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.

Outgoing Sound

Reflected Sound

What is this Navy Ship trying to do ?

Ultrasound = sound higher then we can hear

•like a dog whistle

•like the sonar used by animals and submarines

•echolocation

Infrasound = sound lower then what we can hear

•Elephant stomp

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?

By People:

•Used a lot in teeth cleaning

Class Activity:

W/S Concepts 8-4

AIM: What is an echo?

Homework:

INTERNET QUESTIONS

AIM: What is an echo?