Advertisements
Advertisements
Question
Why do we hear more clearly in a room with curtains than in a room without curtains ?
Advertisements
Solution
We hear more clearly in a room that is curtained than in a room that is uncurtained because curtains are bad reflectors of sound. They absorb most of the sound falling on them, and hence do not produce echoes. On the other hand, in an uncurtained room, there is a greater reflection of sound and thus echoes are formed. These echoes cause a hindrance to hearing. Therefore, we hear more clearly in a room with curtains than in a room without curtains.
RELATED QUESTIONS
Does sound follow the same laws of reflection as light does? Explain.
What is meant by an echo?
Explain why, the flash of lightning reaches us first and the sound of thunder is heard a little later.
Fill in the blank with suitable word :
An echo is simply a ................... sound.
Why are the ceilings of concert halls made curved ? Draw a labelled diagram to illustrate your answer.
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) ?
A man standing 825 metres away from a cliff (steep rock) fires a gun. After how long will he hear its echo ? Speed of sound in air is 330 m/s.
Explain by giving a scientific reason.
We cannot hear the echo produced in a classroom.
State two conditions necessary for hearing an echo.
What are the medical applications of echo?
How can you calculate the speed of sound using echo?
______ allows bats to navigate through dark caves and find insects for food.
What is an echo? Write the conditions to hear an echo.
Numerical problems:
An echo returned in 3s. What is the distance of the reflecting surface from the source given that the speed of sound is 330 ms-1?
Answer the following question in your own words.
What factors are important to get a distinct echo?
