Advertisements
Advertisements
प्रश्न
A man is kidnapped, blindfolded and imprisoned in a big room. How could the man tell if he was in : a bare room
उत्तर
The person would hear echoes when talking in a bare room.
APPEARS IN
संबंधित प्रश्न
Explain why, the flash of lightning reaches us first and the sound of thunder is heard a little later.
Which of the following statement best describes frequency?
What is meant by 'reflection of sound' ? What type of surfaces are the best for reflecting sound ?
Name any two objects which are good reflectors of sound.
What is the minimum distance in air required from a sound reflecting surface to hear an echo (at 20°C) ?
An echo-sounder in a trawler (fishing boat) receives an echo from a shoal of fish 0.4 s after it was sent. If the speed of sound in water is 1500 m/s, how deep is the shoal ?
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 ?
Explain by giving a scientific reason.
We cannot hear the echo produced in a classroom.
______ is an image obtained by the use of reflected ultrasonic waves.
Assertion: The sound which we hear again is called Echo.
Reason: The sensation of sound (Echo) persists in our brain for about 1 s.
