Because echos are created by sound waves bouncing off of walls, and people and furniture block the walls and the space for the echo to bounce back. If you throw a handball at a wall it will bounce back, but if you throw a handball in a room with a bunch of people it will hit one of these aforementioned people and they will be very unhappy, as they have a right to be. SEEWHATIMSAYIN.
because the class is small then 17.2 metres therefore we cannot hear echo.(from jainam )
because it is not full of solids
I would expect to hear an echo in a gymnasium because if you think of a basketball bouncing just 1 you hear it coming right back at you.
Echo
When a sound wave is reflected, you hear an echo.
you can hear a echo in one particular direction because the direction you do it the waves bend back towards you
An echo
we hear an echo because its in our blood to hear things in a repeditive form but a lot quieter.
echo
echo turns into the echo we hear today.
an echo
dolpins hear through an echo
I would expect to hear an echo in a gymnasium because if you think of a basketball bouncing just 1 you hear it coming right back at you.
The gaps between the reflections are long when you hear an echo. When the reflections are very close together then you here no single echo, you hear many close reflections as a reverberation.
It is a record produced by the action of an echo-graph where the echo signal is plotted in the form of graph.
Duck quacks do echo.It is a scientific myth that a duck's quack does not echo. Research has shown that a duck's quack does echo, but it is hard to hear because it is difficult to distinguish the quack from the echo.There are several reasons why it is difficult to hear the echo:Echoes are produced after loud noises. Ducks quack very softly, so the reflected sound is difficult to hear.A reflecting surface is needed to hear an echo. Ducks tend not to live near reflecting surfaces such as cliff faces or buildings. An echo could be heard more readily if the duck quacked whilst flying past such as surface.
echo
Echo
When a sound wave is reflected, you hear an echo.