This experiment is based on Bernoulli’s principle.
All you need for this experiment is a 20 rupee note.
Hold the note with its shorter edge underneath your lower lip. Blow gently onto the upper side of the note. We expect the note to be blown downwards. But surprisingly the note rises up.
This happens due to Bernoulli’s principle. Daniel Bernoulli was a Dutch scientist who did a lot of study on the behaviour of fluids.
He discovered that an increase in the speed of fluid causes a decrease in its pressure.
As we blow on the top of the note, the speed of air increases. This causes a decrease in the pressure on the top of the note. The pressure of air below the note is higher. This pushes the note upwards.