Complete the crossword, then click on "Check" to check your answer. If you are stuck, you can click on "Hint" to get a free letter. Click on a number in the grid to see the clue or clues for that number.
A sound created in a big hall will persist by repeated reflection from the walls until it is reduced to a value where it is no longer audible. The repeated reflection that results in this persistence of sound is called ___________
3.
When we shout or clap near a suitable reflecting surface such as a tall building or a mountain, we will hear the same sound again a little later. This sound which we hear is called an _________
4.
_____________ is a medical instrument used for listening to sounds produced in the body. In this instrument, these sounds reach doctor’s ears by multiple reflections that happen in the connecting tube.
Down:
1.
The roaring of thunder is due to the successive ________ of the sound from a number of reflecting surfaces, such as the clouds at different heights and the land.
2.
The ultrasonic waves allow different tissues such as organs and bones to be ‘seen’ or distinguished by _____________ of ultrasonic waves by the objects examined.