Question 2 :
Presence of excessive or unwanted sounds in the environment is called 

Question 3 :
Which of the following is not caused due to noise pollution?

Question 4 :
Trees must be removed from the road sides and around buildings to reduce the harmful effects of noise pollution.

Question 6 :
The lowest pitch out of the following sources is that of a

Question 8 :
The persistence of hearing for human beings is not more than

Question 9 :
When tuning a violin, a string is tightened. The musical note being played on the string becomes higher in pitch.

Question 10 :
When we hold a thin plastic ruler firmly on a bench:

Question 13 :
A wave moves at a constant speed along a stretched string.<br>Mark the incorrect statement out of the following

Question 14 :
When a sound wave enters the ear, it sets the eardrum into oscillation, which &#160;in turn causes oscillation of 3 tiny bones in the middle ear called ossicles. This oscillation is finally transmitted to the fluid filled in inner portion of the ear termed as inner ear, the motion of the fluid disturbs hair calls within the inner ear which transmit nerve impulses to the brain with information that a sound is present. The three bones present in the middle ear are named as hammer, anvil and stirrup. Out of these the stirrup is the smallest one and this only connects the middle &#160;ear to inner ear as shown in the figure below. The area of stirrup&#160;and its extent of connection with the inner ear limits the sensitivity of the human ear. Consider a person's eat whose moving part of the eardrum has an area of about 43 mm$^{2}$ and the area of stirrup is about 3.2 mm$^{2}$. The mass of ossicles is negligible. As a result, force&#160;&#160;exerted by sound wave in air on eardrum and ossicles is same as the force exerted by ossicles on the inner ear. Consider a sound wave having maximum pressure fluctuation of $3\times10^{-2}$&#160;Pa from its normal equilibrium pressure value which is wqual to $10^{5}$ Pa. Frequency of sound wave is 1200 Hz.&#160;<br/>Data: Velocity of sound wave in air is &#160;332 m/s. Velocity of sound wave in fluid (present in inner ear) is 1500 m/s. Bulk modulus of air is $1.42\times10^{5}$ Pa. Bulk modulus of fluid is $2.18\times10^{9}$ Pa.<br/><br/><br/>Find the pressure amplitude of given sound wave in the fluid of inner ear.&#160;

Question 15 :
A sound of intensity $I$ is greater by $3.0103\ dB$ from another sound of intensity $10\ nW\ c{ m }^{ -2 }$ . The absolute value of intensity of sound level $I$ in ${ Wm }^{ -2 }$ is :<br/>