Which of the following device does not work on the multiple reflections of sound waves?

A. stethoscope B. hydrophone

C. soundboard D. megaphone

The frequencies of four sound waves are given below. Which of these sound waves can be used to measure the depth of sea by the echo method?

A. 15,000 Hz B. 10 kHz

C. 50 kHz D. 10,000 Hz

Which of the following frequency of sound can be generated by a vibrating simple pendulum as well as by the vibrating vocal cords of a rhinoceros?

A. 5 kHz B. 25 Hz

C. 10 Hz D. 15,000 Hz

What type of waves are generated by SONAR device fixed to a fishing ship?

A. water waves B. radio waves

C. sound wavesD. infrared waves

We can distinguish between the musical sounds produced by different singers on the basis of the characteristic of sound called:

A. frequency B. timbre

C. pitch D. loudness