Advertisements
Advertisements
प्रश्न
On which day, a hot day or a cold day, an echo is heard sooner ? Give reason for your answer.
Advertisements
उत्तर
An echo is heard sooner on a hot day because the speed of sound in air increases with increase in temperature of the propagating medium. Therefore, the speed of sound in air is faster on a hot day and thus echo is heard sooner.
संबंधित प्रश्न
An echo returned in 3 s. What is the distance of the reflecting surface from the source, given that the speed of sound is 342 m s−1?
Which property of sound leads of the formation of echoes ?
What is the other name of a loud-hailer ?
Name the device which is used to address a small gathering of people.
Fill in the blank with suitable word :
An echo is simply a ................... sound.
The echo of a sound is heard after 5 seconds. If the speed of sound in air be 342 m/s, calculate the distance of the reflecting surface.
What is meant by 'reflection of sound' ? What type of surfaces are the best for reflecting sound ?
What is an echo ? How is echo formed ?
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.
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.
Answer the following question in your own words.
What is an echo?
What is the minimum distance needed for an echo?
State two conditions necessary for hearing an echo.
How can you calculate the speed of sound using echo?
When sound is reflected from a distant object, an echo is produced. Let the distance between the reflecting surface and the source of sound remain the same. Do you hear an echo sound on a hotter day? Justify your answer.
______ allows bats to navigate through dark caves and find insects for food.
What is an echo? Write the conditions to hear an echo.
Answer the following question in your own words.
What factors are important to get a distinct echo?
