Advertisements
Advertisements
Question
Sunil is standing between two walls. The wall closest to him is at a distance of 660 m. If he shouts, he hears the first echo after 4 s and another after another 2 seconds.
- What is the velocity of sound in air?
- What is the distance between the two walls?
Advertisements
Solution
Given - a distance of the nearest wall from Sunil = 660 m
Time after which Sunil hears first echo, (t1) = `(4 sec)/(2 sec)` = 2 s
Time after which Sunil hears second echo (t2) = `(6 sec)/(2 sec)` = 3 s
Velocity = `"distance"/"time"`
Let d1 be the distance of closest wall.
Let d2 be the distance of the other closest wall.
V = `"d"_1/"t"_1 = 660/2` = 330 m/s
Velocity = 330 m/s
Velocity = `"d"_2/"t"_2`
330 = `"d"_2/3`
330 × 3 = `"d"_2`
`"d"_2 = 990`
Distance between the two walls -
d1 + d2 = 660 + 990 = 1650 m
Distance between the two walls - 1650 m
APPEARS IN
RELATED QUESTIONS
Two children are at opposite ends of an aluminium rod. One strikes the end of the rod with a stone. Find the ratio of times taken by the sound wave in air and in aluminium to reach the second child.
Select the correct alternative :
The speed of sound in water is
Describe an experiment to show that sound can travel in water.
Write the approximate speed of sound in water .
A boy fires a gun and another boy at a distance of 1020 m hears the sound of firing the gun 3 s after seeing its smoke. Find the speed of sound.
A jet aircraft flies at a speed of 410 m/s. What is this speed known as?
Calculate the frequency of a wave whose time-period is 0.02 s.
When we put our ear to a railway line, we can hear the sound of an approaching train even when the train is far off but its sound cannot be heard through the air. Why?
Fill in the blanks with suitable words .
Wave speed in metres per second equals frequency in ............ multiplied by ..................... in ..................
The maximum speed of vibrations which produce audible sound will be in :
A man is kidnapped, blindfolded and imprisoned in a big room. How could the man tell if he was in : a city
Hydrogen gas is filled in two identical bottles, A and B, at the same temperature. The mass of hydrogen in the two bottles is 12 gm and 48 gm respectively. In which bottle will sound travel faster? How many times be as fast as the other?
Write the formula for speed of sound in a gas using Laplace correction.
The velocity of sound in solid is ______ than the velocity of sound in air.
Velocity of sound in a gaseous medium is 330 ms–1. If the pressure is increased by 4 times without causing a change in the temperature, the velocity of sound in the gas is
Velocity of sound in the atmosphere of a planet is 500 ms–1. The minimum distance between the sources of sound and the obstacle to hear the echo should be
A strong sound signal is sent from a ship towards the bottom of the sea. It is received back after 1s. What is the depth of sea given that the speed of sound in water 1450 ms–1?
Establish the relationship between the speed of sound, its wavelength and frequency. If the velocity of sound in air is 340 m s–1, calculate
(i) wavelength when the frequency is 256 Hz.
(ii) frequency when the wavelength is 0.85 m
The propagating disturbance that travels in a medium is called a ______.
On which factors does the speed of sound in the solid medium depend?
