Question

Sound travels the fastest in which of the following mediums?
A. Water
B. Steel
C. Air
D. Kerosene oil

Answer 1

Hint: Sound waves need molecules to propagate as they are longitudinal waves, so they need a medium to travel through. The molecules vibrate and thus pass the vibration of sound from one molecule to another, and thus propagate through either compression or rarefaction.

Complete answer:
We know that sound waves are longitudinal waves. Longitudinal waves need a medium to travel. Longitudinal waves are transported through particles. For sound waves, they travel through compression and rarefaction. They travel through different sequences of waves of pressure through a compressible media.

Sounds can propagate through different media of solid, liquid and gas. Sound waves travel by vibrations of molecules. In fact, when sound travels through different type of media, its speed changes. When sound travels in solid, its speed is more when comparing the speed of sound with respect to liquid and gas. This is because the density of solids is more; hence the molecules are nearer to each other.

Because the molecules are nearer, they collide with each other more frequently; hence the numbers of vibrations are more, so the sound travels faster in denser substances. Thus the speed of sound in air is slower as compared to solids and liquids. Hence as sound travels the fastest in solids, here it travels fastest in steel.

Thus option B is the correct answer.

Note:The speed of sound in air is quite lower as compared to the speed of light in air. This is the reason that when lightning strikes, then we are first able to see it and its sound can be heard after a couple of seconds. Also, light can travel through vacuum as it is radiation while sound cannot travel in vacuum as there is no medium.