Sunil Batra Solutions for Chapter: Sound, Exercise 3: Summative Assessment Some Solved CBSE Sample Questions

On which characteristics of sound wave do the following property depend:
Loudness.

On which characteristics of sound wave do the following property depend:
Pitch.

A man stands between two high rise buildings and blows a whistle. He hears two successive echoes after $0.8$ and $2.4$ seconds. Calculate the distance between the building. [Speed of sound $=330 \mathrm{m} {\mathrm{s}}^{-1}$]

Represent graphically two sound waves having the same amplitude but different frequencies.

A source of sound produces $20$ compressions and $20$ rarefactions in $0.2$ seconds. The distance between a compression and a successive rarefaction is $50\mathrm{cm}$. Find the wavelength and frequency of the wave.

Seema went to an opera house. She appreciated its architecture and furnishings. The curved ceiling, draperies, cushions and curtains were perfectly placed. She also saw a soundboard behind the stage. She now wondered if each of these accessories were placed for the sake of aesthetics of the hall or had a scientific reason too.
What is the purpose of cushions, curtains and draperies in an opera house? 

Seema went to an opera house. She appreciated its architecture and furnishings. The curved ceiling, draperies, cushions and curtains were perfectly placed. She also saw a soundboard behind the stage. She now wondered if each of these accessories were placed for the sake of aesthetics of the hall or had a scientific reason too.
How does the curved ceiling and soundboard help?    

Seema went to an opera house. She appreciated its architecture and furnishings. The curved ceiling, draperies, cushions and curtains were perfectly placed. She also saw a soundboard behind the stage. She now wondered if each of these accessories were placed for the sake of aesthetics of the hall or had a scientific reason too.
List some characteristic quality of Seema.