Class 10 Physics Chapter-11 Sound Latest Notes

SUMMARY

• Sound is produced by a vibrating body. It travels in the medium from one place to another in the form of compressional waves.
• Loudness is a feature of sound by which a loud and a faint sound can be distinguished.It depends upon the amplitude, surface area and distance from the vibrating body.
• Sound energy flowing per second through unit area held perpendicular to the direction of sound waves is called the intensity of sound. bel is unit of the intensity level of sound, where 1 bel = 10 decibels
• Pitch of the sound is the characteristics of sound by which a shrill sound can be distinguished from a grave one. It depends upon the frequency.
• The characteristics of sound by which two sound waves of same loudness and pitch are distinguished from each other is called the quality of sound.
• The sounds with jarring effect on our ears are called noise and the sounds having pleasant effect on our ears are called musical sounds.
• Noise pollution has become a major issue of concern in some big cities. Any form of sound which disturbs the normal functioning of any natural ecosystem or some human community is the cause of noise pollution.
• Noise pollution can be reduced to acceptable level by replacing the rusty noisy machinery with environment friendly machinery and equipments, putting soundreducing barriers, or using hearing protection devices.
• The technique or method used to absorb undesirable sound energy by soft and porous surfaces is called acoustic protection. This can be done by using soft, rough and porous materials.