Transverse waves: Transverse waves are mechanical waves that cause particle motion. The direction of particle motion is orthogonal to the direction of wave motion.

Longitudinal waves: Longitudinal waves are the second kind of wave. In this type of wave, particles move along a straight line parallel to the direction of wave motion, and they do so by undergoing repeated compressions and elongations, e.g. sound waves in the air.

●The quality of a sound is defined as its richness or woodiness. Sound of the same pitch and loudness may be differentiated            from one another depending on the quality of the sound. On the other hand, noise is not pleasant to the ear at all.                      However, they may both have the same loudness and pitch as each other.

●Sound travels at a constant speed. The speed at which sound travels through various materials is varied. The parameters of            the medium, such as pressure, density, and temperature, influence the speed of sound.

●Solids travel at a faster rate than liquids and gases. The speed of sound in air is 331 metres per second at 0 degrees Celsius             and 344 metres per second at 22 degrees Celsius.

●When a source generates sound at a faster rate than the speed of sound in the air, it causes a sonic boom, which causes                 shockwaves to be generated with a significant deal of energy to travel through the air. They make a tremendous amount             of noise, loud enough to break windows and cause structural damage to structures.

1. Describe the process through which your school bell produces sound.

2. Why is the term "mechanical waves" used for sound waves?

3. Will you be able to pick up on any sounds made by your friend if both of you were on the moon?

4. What does it mean when a sound wave is referred to as a longitudinal wave?

5. While sitting among others in a dark room, what aspects of the sound allow you to recognise your friend's voice and identify them as such?

6. A flash and thunder are both created at the same time. However, thunder is heard a few seconds after the flash is seen. Why is this?

7. Does sound obey the same rules of reflection as light? If yes, what are those laws? Explain.

8. The production of an echo occurs when a sound is reflected off of a distant object. Continue to maintain a constant distance between your reflecting surface and the source of your sound output. On a hotter day, do you hear an echoing sound?

Ans 1– When a hammer is struck on the school bell, it slides forwards and backwards, causing compressions and rarefactions as a result of the vibrations. This is how the school bell produces its distinctive ringing sound.

Ans 2– In order for sound waves to travel and interact with the particles existing in a medium, the medium must be transparent. As a result, sound waves are referred to as mechanical waves.

Ans 3– No. In order for sound waves to propagate, they must pass through a medium. Because there is no atmosphere on the moon, and because sound cannot travel in a vacuum, I would not be able to hear any sounds made by my friend if we were on the moon.

Ans 4– A longitudinal wave is a kind of wave that goes parallel to the direction of the wave or along the path of the wave, depending on which is most appropriate. When a sound is produced, the direction in which the particles of the medium vibrate is parallel to the direction in which the disturbance is propagating. As a result, a sound wave is referred to as a longitudinal wave.

Ans 5– The quality of sound is a distinguishing trait that allows us to recognise the voice of specific individuals. Although two persons have the same pitch and loudness of voice, the attributes of those sounds will be different.

Ans 6– The speed of sound is 344 metres per second, whereas the speed of light is 3 x 10^8 metres per second. When measured against the speed of light, the speed of light is slower. Due to this, thunder takes longer to reach the Earth as compared to the speed of light, which is far quicker. As a result, lightning is always seen before thunder occurs.

Ans 7– Yes, sound follows the same rules of reflection as light in terms of refraction. At the point of incidence, the reflected sound wave and the incident sound wave both create an identical angle with the normal to the surface of the object. Aside from that, the incident sound wave, the normal to the point of incidence, and the reflected sound wave are all located in the same plane.

Ans 8– It is possible to hear an echo if the time delay between the reflected sound and the original sound is at least 0.1 seconds. When the temperature of a medium rises, the speed of sound in that medium rises as well. The time interval between the reflected and original sound will decrease on a hotter day, and an echo is heard only if the time interval between the reflected and original sound is longer than 0.1 seconds on such a day.

Essentially, sound is a form of mechanical energy that causes the sensation of hearing to be perceived. The vibration of various things results in the production of sound. The sound wave propagates across the medium as compressions and rarefactions. Sound waves are waves that travel in a straight line. It is critical that you comprehend this chapter completely in order to master this concept of physics in the future.