Applications of Reflection of Sound

Q. What are the important formulas used in chapter sound?

Q.

Stethoscope utilizes the principle of ___________.

Q.

Derive the minimum distance to hear a distinct echo by the obstacle from the source.

Q.

Why our voice echos in an empty room but doesn't echo in a room filled with lots of furniture and other things ?

Q. A man is standing between two cliffs and fires a gun. He hears 2 successive echoes after 3s and 5s. find the distance between 2 cliffs?

Q. What are the conditions required to hear a distinct echo?

Q.

A stethoscope utilizes the principle of_______________.

Q. ntAn echo repeats two syllables. If the velocity of sound is 330 m/s, the the distance of the reflecting surface isn

Q. Question 20
A sonar device on a submarine sends out a signal and receives an echo 5 s later. Calculate the speed of sound in water if the distance of the object from the submarine is 3625 m.

Q.

a man slaps his hand near a mountain and hears the Eco after 4 seconds. if the speed of sound under these conditions be 330 meter per second what is the distance of mountains from the man :-

A) 660 m

B) 440 m

C) 330 m

D) 550 m

Q.

Which of the following is the technique used in ships to calculate the depth of ocean beds?

1. SONAR

2. LASER

3. Reverberation

4. Sonic boom

Q.

How far away is the cliff from the child, if a child hears an echo from a cliff 6 second after the sound produced by powerful horn? The velocity sound in air at 22^oC is 344 m/s.

1. 688 m

2. 1000 m

3. 58 m

4. 1032 m

Q.

Minimum time interval for hearing a distinct echo is

1. 1.5 s

2. 2.0 s

3. 0.2 s

4. 0.1 s

Q. A soldier standing between two building fire a gun. he hear the echo of sound from the first building after 2 second hand Eeco from the 2nd building after 3 second find the distance between two building. ( Speed of sound in air = 340 m/s)

Q.

A soldier walks toward a high wall making 120 steps per minute.When he is at a distance of 85cm from the wall, he observes that the echo of a step coincides with the next step.The speed of sound isa)85m/s b)170m/s c)980m/s d)exactly 340m/s

Q.

If a child hears an echo from a cliff 6 second after the sound is produced by shouting, how far is the cliff? Take speed of sound to be 343.33 ~m/s

1. 58 m

2. 1030 m

3. 68 m

4. 990 m

Q. You must have seen the doctor checking the sounds produced in the chest of a patient using medical instrument called stethoscope. On what principle does this stethoscope works?

1. Absorption
2. Multiple reflections
3. Single reflection
4. Beats formation

Q. a boy stands 60 m infront of a wall and claps . he continues to clap every time an echo is heard . another boy finds that time taken between 1st and 51st clap is 20s find the speed of sound in air .

Q. Which of the following techniques is used for identifying object location under water?

1. SONAR
2. RADAR
3. GPS
4. LASER

Q. If the sound speed in water is 1480 m/s. Calculate the minimum distance to hear echo in water.​

1. 54 m​
2. 64 m​
3. 74 m​
4. 84 m​

Q. What will be the minimum distance to hear a distinct echo if the speed of sound for ${22}^{0}C$ in air is 344m/s?

1. 34.4 mm
2. 16.5 m
3. 17.2 m
4. 20 m

Q. Which of the following use echolocation?

1. Bats
2. Dogs
3. SONAR
4. RADAR

Q.

What does the acronym SONAR stand for?

1. Sound Navigation and Ranging

2. Sound Notification and Ranging

3. Sound Notification and Reverberation

4. Sound Navigation and Reverberation

Q. A ship sends a sonar wave to the sea bed which is flat and measured several times over a large area. One day the reflected sound wave takes longer time than in previous measurements. The possible reason is:

1. The frequency of the sonar wave, generated by the equipment is higher than previous measurements.
2. There is a solid object of large size in the path of sonar wave.
3. There is a huge air bubble in the path of sonar wave.
4. The loudness of the sonar wave, generated by the equipment is lower than previous measurement.

Q. Which of the following devices / organisms uses echolocation?

1. Bats

2. Dogs

3. SONAR

4. Telescope

Q. The technique used by bats for navigation and location of food is:

1. Reflection of light
2. Echocardiography
3. Ultrasonography
4. Echolocation

Q.

A boy stands 80m away from a high wall and claps. He continues to clap as soon as he hears an echo. Another boy records that the time taken between the first clap and eleventh clap is 3s. Calculate the speed of sound.

Q. a girl stand at a distance of 170m in front of a high wall and claps. what will be the time interval when she hears its echo? [speed of sound = 540 m/s

Q. A man standing at a distance from a hill fires a gun an hears its echo after 4.7 sec. He , then, moves 300 m closer to the hill and fires the gun. Echo of this sound is heard after 2.9 sec. What is the velocity of sound?

Q. Question 12
A girl is sitting in the middle of a park of dimension $12m\times 12m$. On the left side of it there is a building adjoining the park and on right side of the park, there is a road adjoining the park. A sound is produced on the road by a cracker. Is it possible for the girl to hear the echo of this sound? Explain your answer.