$(i)$ Which property of sound wave determines:
$(a)$ loudness
$(b)$ pitch?
$(ii)$ $A$ $SONAR$ station picks up a return signal after $3 \ s$. How far away is the object? (Speed of sound in water is $1440 \ m \ s^{-1}$)
$(iii)$ How can reverberations in a big hall or auditorium be reduced?

(N/A) $(i)$
$(a)$ Loudness is determined by the amplitude of the sound wave.
$(b)$ Pitch is determined by the frequency of the sound wave.
$(ii)$ Given: Time taken $(t)$ = $3 \ s$,Speed of sound in water $(V)$ = $1440 \ m \ s^{-1}$.
The distance $(S)$ is calculated as: $S = (V \times t) / 2 = (1440 \times 3) / 2 = 2160 \ m$.
$(iii)$ Reverberations in a big hall or auditorium can be reduced by covering the walls and ceiling with sound-absorbent materials such as compressed fibreboard,rough plaster,or draperies. Additionally,seats can be covered with sound-absorbing materials.