Question

_______ varies directly with vibrating body's amplitude.
1. Loudness of sound
2. Modulation of sound
3. Quality of sound
4. Tone of the sound

Answer 1

Correct Answer - Option 1 : Loudness of sound

The correct answer is Loudness of sound.

• The loudness of a sound depends directly on the amplitude of the vibrating body i.e. if the amplitude is large then the sound is also loud.
  • Loudness is directly proportional to the square of the amplitude of vibration.
  • The loudness is expressed in decibel (dB).
  • Sound above 80 dB is generally harmful to human ears.
  • Noise above 70 dB over a prolonged period of time may also damage hearing.

• The maximum displacement of a wave on either side of its mean position is called amplitude.
• The process of superimposing a low-frequency signal on a high-frequency carrier signal is called Modulation of Sound. 
  • It is of three types:
    • Amplitude modulation:- Amplitude of carrier wave is modulated according to the signal wave.
    • Frequency modulation:- The frequency of the carrier wave is modulated according to the signal wave.
      • The number of waves that pass a fixed place in a given amount of time is called the frequency of the wave. 
    • Phase modulation:- It is the process of transmitting information over a carrier wave by changing its phase according to the amplitude signal wave.
      • The phase involves the relationship between the position of the amplitude crests and troughs of two waves.
      • If the peaks of two signals with the same frequency are in exact alignment at the same time, they are said to be in phase.
•  Those characteristics of sound which allow the ear to distinguish sounds that have the same pitch and loudness is called sound quality or timbre.
•  The tone is defined as the sound which is recognized by its regularity of vibrations.