Erika visits the Grand Canyon with her family. When she shouts near the edge, she can hear her voice echo throughout the canyon. Which statement describes why Erika hears her echo? A. The sound was loud. B. The sound waves travelled in a vacuum. C. The sound waves reflected off the canyon walls. D. The sound waves bent as they travelled into the canyon.

Uttam and Nitesh are standing at 12 m and 20 m respectively from a cliff. They startshouting their names. They want to hear clear echo of their sound.(a) Will Nitesh and Uttam be able to hear a clear echo of their own sound?(b) Can you explain the condition for a sound to form an echo?

Name the waves used for echo depth sounding.(b) Give one reason for their use in the above application.

A group of hikers hears an echo 3.50 s after shouting. How far away is the mountain that reflected the sound wave? (Assume the speed of sound is 343 m/s.) m

You can hear an echo when the sound wave reflects from the wall and reaches you.If you hear an echo, 4 seconds after you produce the sound, how far is the wall?Use a speed of sound of 340 m/s for this question.  340 meters away from you You Answered  1360 meters away from you Correct Answer  680 meters away from you   10 meters away from you

Which of the following is an example of hearing rather than listening?Multiple ChoiceHe heard what she said and responded with an appropriate answer.The sound of firecrackers filled the nighttime air.He heard the sound outside and decided that the noise must have been a car accident.She heard his cry for help and reacted by immediately calling the rescue squad.