Q.1. Choose the correct option.
(i) The pitch of sound depends on
a. frequency b. amplitude (c) both of these (d) none of these
(ii) In order to reduce the loudness of a sound we have to
(a) decrease its frequency of vibration of the sound.
(b) increase its frequency of vibration of the sound.
(c) decrease its amplitude of vibration of the sound.
(d) increase its amplitude of vibration of the sound.
(iii) Loudness of sound is measured in units of
(a) decibel (dB) (b) hertz (Hz) (c) metre (m) (d) metre/second (m/s)
Q.2 Fill in the blanks.
a. The vibrations of a simple pendulum are also known as ...................
b. The number of vibrations completed in one second is known as .............
c. ................ is proportional to the square of amplitude.
Q.3 Enlist the characteristics of sound. Which of these is related to the amplitude of vibration?
Q.4 A pendulum oscillates 20 times in 4 seconds. Find its time period & frequency.
Q.5 We have a stringed musical instrument. The string is plucked in the middle, first with a force of greater
magnitude and then with a force of smaller magnitude. In which case would the instrument produce a
louder sound?
Answers
HI, HERE IS YOUR ANSWER:
Q1)1) frequency
2) decrease its amplitude of vibration of the sound.
3) decibel
Q2)1)oscillation
2) frequency
3) intensity of a wave
Q3)When the amplitude of vibration is large ,the sound produced is loud. If the amplitude of vibration is small ,the sound produced is feeble. The loudness of sound is directly proportional to the square of amplitude of vibration. If the amplitude of vibration is doubled ,then the loudness will become 4 times.
Q4)The time period and frequency are 0.25 sec and 4 Hz.
Q5)The loudness of sound depends upon the amplitude of vibration. The amplitude of string is larger when it is plucked with greater force and hence the sound will be louder in that case.
HOPE IT HELPS YOU!!!1
Answer:
Q.1 The pitch of sound depends on frequency.
Q.2 In order to reduce the loudness of a sound we have to decrease the amplitude of vibration of sound.
Q.3 Loudness of sound depends on the amplitude of vibration. Higher the amplitude of vibration, louder is the sound produced.