The document is a student's notes on sound waves from a class. It recaps key concepts about sound waves, including that time period varies inversely with frequency, and speed of sound decreases from solids to gases. It also contains review questions on how the eardrum responds to sound waves, the relationship between wave velocity, frequency, and wavelength, and calculating time period, frequency, and time taken for a sound wave to travel a distance. References at the end include the textbook, websites, and YouTube videos used in the lesson.

1. SONAL BHARAL (23)
111 A Critical Understanding of ICT
F.Y.B.ED
TILAK COLLEGE OF EDUCATION
TheMusic of Sound
MSCERT - IX
Prof. Incharge: Prof. Sonpethkar

16. RECAP:-
State true or false:-
1. The time period varies inversely as frequency.
FALSE TRUE
2.The speed of sound decreases when we go from solid to gaseous state.
TRUE FALSE
3. Sound gets reflected just like light.
TRUE FALSE
4.Vibration is nothing but the oscillatory motion of a body.
FALSE TRUE
5.Reverberation is the repeated of sound that results in its persistence.
TRUE FALSE

17. APPLICATION
1.What happens to the eardrum when a sound wave approaches it?
2.The wave velocity (v), frequency of the wave (f) and its wavelength (λ) are related by the
formula____________
3.What happens to the sound made by an electric bell when the air is slowly sucked out of the
jar using a vacuum pump?
4.If the wavelength of a wave moving with a velocity 20 m/s is 5 cm,
calculate its time period and frequency.
5.Frequency of a sound wave is 2000 Hz and its wavelength is 20 cm. Calculate the time taken
by the wave to move through 2 km.

18. REFERENCE:-
*MSERT,2010, “Science and Technology”, Std IX
*www.slideshare.net/josteach/sound-and-waves-grade-6-pps
*www.google.co.in/webhp?sourceid=chrome-
instant&ion=1&espv=2&ie=UTF-8#
*https://www.google.co.in/webhp?sourceid=chrome-
instant&ion=1&espv=2&ie=UTF-8#
Youtube videos:-

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