Concise Physics Class 9 ICSE Solutions for Chapter 8 - Propagation of Sound Waves
Q1. Can Sound Travel in the Air? Explain in Brief.
Ans: Sound travels through any medium viz: solid, liquid and gas. However, it cannot travel through a vacuum.
If you see any object moving forward, it pushes and compresses the air, thereby making a space of high pressure. With this back and forth movement, there are a series of rarefaction and compression created in the air. This lets the sound wave propagating through the media.
Q2. What is the Speed of Sound in Different Media?
Ans: The speed of sound in different media depends on the conditions below.
It depends on the properties of the medium.
It also depends on the temperature and pressure of the medium.
It decreases when we move from solid to a gaseous state
With the rise in temperature, the speed of sound also rises.
Q3. Does the Speed of Sound in the Air be Affected by Temperature?
Ans: The speed of sound in air varies. The speed rises by 0.6 m/s for every 1°C rise in temperature.
Q4. Describe the Production of Sound.
Ans: Sound is produced because of the vibration of objects.
Clapping of palms
Vibration produced by strings
Beating a diaphragm of a drum
By flute due to vibration of air-column
By guitar because of vibration of it strings
In the examples mentioned above, their amplitude is too less that one cannot see, but can feel.