Question

When we inhale Helium gas funny sound appear which is due to:
A.High density of helium that air
B.Low density of air than helium
C.Low density of helium than air
D.Reaction between air and helium

Answer 1

Hint: Air contains gases such as nitrogen, oxygen, carbon dioxide etc. Helium is the second element of the periodic table or the first noble gas and has a molar mass of just 4 amu.

Complete step by step answer:
The above phenomena occurs due to change in speed of light when it goes to a less dense medium. Helium is very lighter in comparison to the other gases present in air. It is also very small in size. Hence this makes the density of helium less than air. Air consists of about 78 percent nitrogen, which has an atomic mass of 14 amu. The mass of nitrogen is approximately 7 times than that of helium. So if sound travels in air though any speed then in the presence of helium it will move faster. The will make helium to travel your vocal tracks twice or thrice in the same time as air traveled once. So other people hearing you hear a quirky or funny sound. However it does not affect the pitch of voice, it just affects our timbre. That is the one which determines the quality of sound and distinguishes one type of sound from another. This all happens due to the lower density of helium than air.

Hence the correct option is C.

Note:
A lighter gas such as helium has higher speed and causes the funny sound. In the same way we can think of gases heavier than air which have lower speed such as Xenon and sulphur hexafluoride. They make our sound more sender and richer. Inhaling the helium is not good for our health because it will make us feel dizzy. In the presence of helium, oxygen consumption of the body decreases.