<< Back to Lessons Index

Science_Lab_Yellow / Lesson 8: What Can Echoes Do?

What Can Echoes Do

What will we be learning today?

  • In this lesson, we are going to learn all about what echoes can do.

What Can Echoes Do?

  • Sonar, or so und navigation and ranging, uses sound waves to detect objects far away. A sonar technician sends out sound waves and then times how long those sound waves take to bounce off distant objects and return.

  • What if a sonar technician on a ship sends out a sound wave toward the ocean bottom? Sound waves travel about 1,500 meters per second in water.

What if the sound wave takes two seconds to return to the ship? The technician will know that the sound wave took one second to reach the ocean floor and then one second more to bounce back to the surface. He or she will conclude that the ocean is 1,500 meters deep.

  • Many animals find things around them with a form of sonar called echolocation. Whales and dolphins bounce sound waves off objects to find out how far away they are.

Bats are able to live in dark caves because they use a form of echolocation rather than sight to navigate. Bats send out high-pitched squeals and clicks into the air at their prey. Their large, forward-pointing ears pick up the echoes. Using this information, bats can close in on their prey.

Let's Review What We Learned Today!

  • Now complete your worksheet!