1What is reflected sound? Explain why an echo is a reflected sound.
2What is echolocation? How does a bat use it?
3Describe how an ultrasonic ruler measures distance.
4What is SONAR? Write the work of a fathometer.
5What is acoustic protection? Why is it needed in a sound recording studio?
6Name two security devices based on reflected ultrasound and state how they work.
7What is ultrasound? Why can we not hear it?