Saturday, April 9, 2011

My Opinion About the Matter: Bernoulli's Principle


Bernoulli's Principle of Fluid Dynamics states that:

"In a steady flow of fluid, the velocity is inversely proportional to the internal pressure of that particular fluid"

It took me awhile to digest this principle out. WHY??
Firstly it states that the increase velocity leads to the decrease in pressure. I carried out an amateur test when I was in Form Four  in the toilet to prove it haha, kid's mind and the result was seemingly reject Bernoulli's belief. 

1. I attached a rubber hose to a water tap.
2. I turned the water tape on so that a medium amount of water will flow (this indicates that the water is running in low velocity).
3. Once the water flowed, I pressed the end of the rubber hose to the floor. You will see that the water flow to every direction (in this state, the water came out of the hose in a low rate).
4. I put my finger perpendicular to the area where the water came out, until I felt the water hit my skin.
5. I wounded the water tap to the maximum. Water will be in high velocity, then. (You will see that the water is coming out from the end of the hose in a higher rate).
6. I put my finger the same way I did, to the same area (given that the end of hose did not move).
7. I felt that the latter pressure which hit my skin was higher, compared to the former test.

Came the 32,000 dollars question: Why?
According to Bernoulli, the higher the velocity, the lower the pressure. So why did I feel a higher pressure exerted on my skin as I turned the water to its maximum speed?

(to be continued..)


  1. hurm, experiment ko kurang sesuai..

  2. Belum habis bha.. ada sambungan lagi. Anyway, thanks

  3. bh.. sambung laa... mo tgk apa hasilnya...


Ohana :)