wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Two light balls are suspended with light strings very close to each other. What happens when we blow air between the balls?


Open in App
Solution

Concept used:

  1. Pressure and velocity both are the macroscopic parameters governing plenty of natural phenomena. Pressure is the measure of force per unit area. Velocity is the measure of the rate of change of displacement.
  2. In thermodynamics, for any in-compressible, non-viscous fluid, the relation between pressure and velocity is given by Bernoulli’s equation.

P+12ρv2+ρgh=Constant

Where, P is the pressure of the in-compressible, non-viscous fluid, ρ is the density of the in-compressible, non-viscous fluid, v is the velocity of the in-compressible, non-viscous fluid, g is the acceleration due to gravity, and, h is the vertical height of the pipe from the reference level.

Explanation:

  1. Pressure and velocity are inversely proportional to each other. If pressure increases, the velocity decreases to keep the algebraic sum of potential energy, kinetic energy, and pressure constant.
  2. Similarly, if velocity increases, the pressure decreases to keep the sum of potential energy, kinetic energy, and pressure constant.
  3. When we blow air between two balls, suspended with light strings, and the velocity(v) of flow increases, the pressure(P) decreases hence the lower pressure created attracts the balls towards each other as the pressure(P) created is much lower than the standard atmospheric pressure, which is in accordance with the Bernoulli’s theorem.

flag
Suggest Corrections
thumbs-up
6
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Variation of Pressure in Fluids
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon