Introduction to Sound Waves

Q. Why do we have two ears

Q. I Want to know about persistence of hearing..
please reply soon..

Q.

Why does sound require a medium to propagate why can't it propagate in vacuum?

Q. Why is hearing affected while going up or coming down from the hills?

Q.

Sound is produced by vibration.

1. True
2. False

Q. The characteristic of sound which distinguishes a sharp sound and dull sound is called.......?

Q.

Question 1
Sound can travel through

(a) gases only
(b) solids only
(c) liquids only
(d) solids, liquids and gases.

Q. Write any three musical instruments that you know and explain how they produce sound. [2 marks]

Q. Question 3
Which of the following statements are correct?
(i) Sound is produced by vibrations.
(ii) Sound requires a medium for propagation.
(iii) Light and sound both require a medium for propagation.
(iv) Sound travels slower than light.

(a) i, ii and iv only
(b) i and ii only
(c) i, ii and iii only
(d) ii, iii and iv only

Q. Question 1
In which of these mediums can sound travel?
(i) Wood
(ii) Water
(iii) Air
(iv) Vacuum

Q.

Which medium does sound produce large

Q.

Choose the correct option:

Statement 1: Sound cannot travel in vacuum.
Statement 2: Sound is a mechanical wave and propagates as an oscillation of particles through the medium. So they cannot travel in vacuum.

1. ​Both statements are wrong

2. Statement 1 is correct but statement 2 is not a correct explanation of it

3. Statement 1 is wrong but statement 2 is correct

4. Statement 1 is correct and statement 2 is correct explanation for it

Q. Four test tubes are filled with different levels of water as shown below. When air is blown from the top of a test tube mouth one by one, identify which test tube will produce a high-pitched sound.

1. S
2. Q
3. R
4. P

Q.

Question 3 (a)
State whether the following statement is true or false.
(a) Sound cannot travel in vacuum.

Q.

What is meaning of magnitude??

Q.

A carbon microphone is best used in a

1. dynamo

2. telephone

3. transformer

4. none of these

Q. Question 1
In which of these mediums can sound travel?
(i) Wood
(ii) Water
(iii) Air
(iv) Vacuum

Q. Sound is a form of energy that produces a sensation of ________ in our ears.

Q.

Sound can travel through

1. gases only

2. solids only

3. liquids only

4. solids, liquids and gases.

Q.

When you pluck the string at one end clamped at both ends, you hear a loud sound.

1. True

2. False

Q. Which among the following statements is true?

1. Sound moves very slowly in the outer space.
2. Intensity of sound gets reduced in the outer space.
3. Shrillness of sound gets reduced in outer space.
4. Sound cannot propagate in outer space.

Q. We have two ears because:
i) It helps our brain to sense that from which direction sound is coming.
ii) In case of hearing loss in one ear the person can still hear from another.

1. Both statements are true.
2. Both statements are false.
3. Statement (i) is only true.
4. Statement (ii) is only true.

Q. Two astronauts are floating close to each other in space. Can they talk to each other without using any special device? Give reason.​

Q. Does reflection of sound also undergoes the laws of reflection.
Laws of reflection state s that incident ray normalray reflected ray and emergent ray will lie in a same plane , 2. Incident ray is equal to reflected ray.and this is true in reflection of light .is it relative to reflection of sound?

Q.

If the wavelength of a sound wave is 40 cm and the time period T = 0.0005 s, then it takes ___ seconds to travel 4 km.

Q.

What a sound does in everyday life?

1. humans communicate with each other

2. Only humans communicate with each other

3. Only animals communicate with each other

4. animals understand humans language using a sound

Q.

Astronauts in space need not necessarily have any electronic device with them to communicate

1. False

2. True

Q. Sir why do we have to ears, only to make out the direction or if one ear loses its ability to hear then other can also hear

Q. Sound travels the fastest inmedium.

1. solid
2. liquid
3. gaseous

Q. If we can only hear things when it compresses air
and reaches our ear .Then how can a man standing out side a closed room can hear a man's sound which is inside the room