Pradeep Singh and Jatinder Singh Solutions for Chapter: Sound, Exercise 1: CHAPTER TEST

A sound wave of length $70 \mathrm{cm}$ travels $840 \mathrm{m}$ in $25 \mathrm{seconds}$. What is the velocity and frequency of sound?

Note: This question given in the book seems to have error and the modified question should be as given below.

An echo is heard after $0.8 \mathrm{seconds}$, when a person fires a cracker $132.8 \mathrm{m}$ from a high building. Calculate the speed of sound.

A source of wave produces, $40 \mathrm{crests}$, and $40 \mathrm{troughs}$ in $0.4 \mathrm{seconds}$. Find the frequency of the wave.

Why an echo is not heard when distance between source of sound and reflecting body is $10 \mathrm{m}$ ?

The distance between the crest and trough of a transverse wave is $15 \mathrm{cm}$, what is the velocity of the wave if its frequency is $1000 \mathrm{Hz}$ ?

In which case is the speed of sound more, the humming of a bee or the roaring of a lion ?

When is the velocity of sound more, during winters or during summers ?

Can elephants hear frequencies less than $20 \mathrm{Hz}$ ?