Fill in the blanks with suitable words.
(a) Time taken by an object to complete one oscillation is called ................... .
(b) Loudness is determined by the .........................of vibration.
(c) The unit of frequency is..........................
(d) Unwanted sound is called ......................... .
(e) Shrillness of a sound is determined by the ................. of vibration.
(a) Time period
Time period may be defined as the time taken by an object or a body to complete the one oscillation or a cycle.
(b) Amplitude
Amplitude shows the loudness of the sound. When the amplitude of the vibration is larger, then the sound produced will be very loud. When the amplitude is small then the produced sound will be feeble.
(c) Hz
Hertz is the unit of frequency. Frequency may be defined as the number of oscillation in one second.
(d) Noise
The sound which is unpleasant and unwanted to ears known as noise whereas the sound which us pleasant to the ears is known as music.
(e) Pitch
If the frequency of the vibration is higher, then the produced sound will be shrill and it has high pitch whereas if the frequency of vibration is lower, then the sound will contain lower pitch.
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- NCERT Chapter