Refraction of Sound
Question 1: What is meant by Refraction of Sound?
Answer:
The bending of the sound waves when they enter a medium where the speed is different is known as the refraction of sound.
Question 2: What is an Echo?
Answer:
An echo is a sound caused by the reflection of sound waves from a surface back to the listener. It is the reflection of sound, arriving at the listener sometime after the direct sound.
Question 3: What are the laws of refraction of light?
Answer:
There are two laws of refraction,
- The incident ray, the refracted ray, and the normal to the interface at the point of the incident all lie in the same plane.
- The ratio of the sine of the angle of incident and the sine of the angle of refraction is constant for given pair of media
Question 4: State two conditions for an echo to take place.
Answer:
The necessary conditions for the formation of an echo,
- The minimum distance between the source of sound and the reflecting body should be 17 meters.
- The wavelength of sound should be less than the height of the reflecting body.
Question 5: What do you mean by the reflection of sound?
Answer:
The reflection of sound is actually similar to the reflection of light. Sound abides by different laws of reflection, in which the angle of incidence does prove equal to the angle of reflection. In addition, sound rebounds from the surface of either solid or liquid similar to a billiard ball. For successfully experiencing the reflection of sound, it is important that the surface should be polished or rough, and that too of a considerably large size.
Question 6: What is the condition for the reflection of a sound wave?
Answer:
The two laws concerned with sound reflection are as follows:
- The incidence angle will always be equal to the reflection angle.
- The incident sound waves, the normal at incidence point and reflected wave, all rest in a common plane.
Question 7: Name a device in which the reflection of a sound wave is used.
Answer:
Stethoscope: A stethoscope is a medical diagnostic instrument based on multiple reflections of sound waves. This is used by doctors for listening to the sounds produced inside the body, particularly in the heart or lungs.
Refraction of Sound
A sound is a vibration that travels as a mechanical wave across a medium. It can spread via a solid, a liquid, or a gas as the medium. In solids, sound travels the quickest, comparatively more slowly in liquids, and the slowest in gases.
A sound wave is a pattern of disturbance caused by energy travelling away from the sound source. The constituents of sound are longitudinal waves. This demonstrates that vibrational particle propagation and the direction of energy wave propagation are parallel. When made to vibrate, atoms begin to oscillate. This continuous back-and-forth motion results in the formation of a high-pressure and a low-pressure zone in the medium.
These high- and low-pressure zones are called compressions and rarefactions, respectively. As a result of these locations transmitting to the surrounding media, the sound waves go from one to the other.