Maharashtra Board Class 7 Science Solution Chapter 18 – Sound : Production of Sound
Balbharati Maharashtra Board Class 7 Science Solution Chapter 18: Sound : Production of Sound. Marathi or English Medium Students of Class 7 get here Sound : Production of Sound full Exercise Solution.
Std |
Maharashtra Class 7 |
Subject |
General Science Solution |
Chapter |
Sound : Production of Sound |
(1) (a) Sound is generated by the rhythmic vibration of an object.
(b) The frequency of sound is measured in HZ.
(c) If amplitude of sound is decreased, its loudness also decreases.
(d) A medium is necessary for propagation of sound.
Group-A |
Group-B |
(a) Flute |
(3) Vibration in the air |
(b) Frequency |
(4) Measured in HZ |
(c) Sound level |
(5) Decibel |
(d) Ultrasonic sound |
(2) Frequency more than 20,000 HZ |
(e) Infrasonic sound |
(1) Frequency less than 20 HZ. |
(3) (a) We know, sound passes faster through solids than gasses so in earlier times, people used to listen for arrival of distant train by putting their ear to the rail.
(b) The sound produced by a table and a sitar are different because of the difference in the pitch.
(c) We know sound cannot pass thought vacuum since there is no air on moon, we cannot hear sound on the moon.
(d) The sound produced by the movement of mosquito’s wings is audible for human being where the sound produced by the movement of our hands are not audible for us. So we cannot hear the movement of our hands.
(4) (a) Sound is generated by the rhythm vibration of an object. We can hear the sound as long as the objects vibrate.
(b) Intensity of sound depends on the amplitude of vibration of the sound.
(d) Frequency on pitch of vibrating of a stretched string can be changed by varying the tension in the string and thickness of the string.