Additional Questions With Solutions
Ques: What is sound?
Ans: When an object vibrates, it produces sound.
Ques: What is eco sound?
Ans: When any sound reflects by striking on any medium, that sound heard us again and again. This is called eco sound.
Ques: What is minimum audible range for human ears?
Ans: The audible range is 20 Hz to 20,000 Hz.
Ques: What is minimum audible distance from sound source to barrier medium?
Ans: 17.2 m.
Ques: What is S.I unit of frequency?
Ans: Hz (Hertz).
Ques: What is S.I unit of wave length?
Ans: S.I unit of wave length is meter.
Ques: By what organ human produces sound?
Ans: Vocal cord. (Larynx)
Ques: How do we produce sound?
Ans: Two vocal cords, are stretched across the voice box or larynx in such a way that it leaves a narrow slit between them for the passage of air When the lungs force air through the slit, the vocal cords vibrate, producing sound.
Ques: In which mediums sounds propagate?
Ans: Solid, liquid and gas.
Ques: In which medium sound does not propagate?
Ans: Vacuum.
Ques: What is eardrum?
Ans: The shape of the outer part of the ear is like a funnel. When sound enters in it, it travels down a canal at the end of which a thin membrane is stretched tightly. It is called the eardrum.
Ques: Write the function of eardrum.
Ans: The eardrum sends vibrations to the inner ear.
Ques: What is oscillatory motion?
Ans: The to and fro motion of an object is known as vibration. This motion is also called oscillatory motion.
Ques: What is frequency? Write is its S.I unit?
Ans: The number of oscillations or vibrations per second is called the frequency of oscillation. The frequency is expressed in hertz (Hz).
Ques: On which measure does loudness of sound depend?
Ans: On its amplitudes.
Ques: What are two important properties of sound?
Ans: Amplitude and frequency are two important properties of any sound.