Which of the following phenomena does not involve the viscosity of air

1.	Which of the following phenomena does not involve the viscosity of air at all? (a) A meteorite burns up on entering the earth’s atmosphere. (b) Raindrops falling from a great height reach the ground with a relatively small velocity. (c) A ball spinning through air can move sideways. (d) In air flowing through a tube of variable cross section, the pressure becomes different at different points.
Answer» Correct Answer is: (d) The change in pressure with velocity is due to Bernoulli’s principle, and is not affected by viscosity.

Which of the following phenomena does not involve the viscosity of air at all? (a) A meteorite burns up on entering the earth’s atmosphere. (b) Raindrops falling from a great height reach the ground with a relatively small velocity. (c) A ball spinning through air can move sideways. (d) In air flowing through a tube of variable cross section, the pressure becomes different at different points.

Answer»

Correct Answer is: (d)

The change in pressure with velocity is due to Bernoulli’s principle, and is not affected by viscosity.