$A$ continuous disturbance is created on the surface of water in a ripple tank with a small piece of cork floating on it. Describe the motion of the cork. What does this tell us about the disturbance?

Name the subjective property of sound related to its frequency and of light related to its wavelength.

$A$ stretched wire $0.5\, m$ long is made to vibrate in two different modes as shown in diagrams $(A)$ and $(B)$ given below:
$(i)$ If the wavelength of the wave produced in mode $(A)$ is $1\, m$,what is the wavelength of the wave produced in mode $(B)$ of the following diagram?
$(ii)$ In which case is the note produced louder? Give a reason for your answer.
$(iii)$ In which case is the pitch of the note produced higher? Give a reason for your answer.

$A$ man stands between two high-rise buildings and blows a whistle. He hears two successive echoes after $0.4 \, s$ and $2.0 \, s$. Calculate the distance between the buildings. (Assume the speed of sound $v = 332 \, m/s$)

What is echo ranging? State any one application of this technique.

Give one example each of natural vibration,forced vibration,and resonance.