Daniel Bernoulli discovered Bernoulli's principle in the 1700s through experiments observing water flow. Bernoulli's principle states that as the speed of a fluid increases, the pressure decreases. It explains that the pressure is lowest where the flow speed is highest. Some applications of this principle are how aircraft wings generate lift through differences in air pressure above and below the wing, and how ventilation works through higher pressure pushing lower pressure areas.

1. BERNOULLI’S PRINCIPLE
SCIENCE FORM 5

2. The History of Bernoulli’s Principle
Daniel Bernoulli
(1700-1782)
 The Swiss mathematician and physicist
discovered the Bernoulli's principle.
 He found the concept of Bernoulli’s
principle when doing the experiment of
water flow through the container.

3. Bernoulli’s Principle
• He observed that the water level
at the centre is the lowest.
• He made some assumptions:
a) As fluid moves from a wider
pipe to a narrower one, the
speed of water flow will be
increase.
b) As the speed of water flow
increase, the pressure will
decrease and the water
cannot go up the upside of
pipe easily.
• Hence Bernoulli's conclusion: the
slower the rate of flow, the higher
the pressure, and the faster the
rate of flow, the lower the
pressure.

4. B RNOUL I’S
E L
PRINCIP E
L
states that
The pressure is inversely proportional to the
speed of a moving fluid.
a)If the speed is high, the pressure is low.
b)If the speed is low, the pressure is high

5. The Effects of Bernoulli’s Principle
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7. Aerofoil
Uplift force

8. Application of Bernoulli’s Principle In Life
• When an aeroplane
moves forward, air
moves faster at the top
of the aerofoil than
below it.
• This creates a low
pressure condition on the
top of the aerofoil.
• The higher pressure at the bottom of the aerofoil will push it up
to produce an uplift force.
• To fly, the upthrust must be greater than the weight of the
aeroplane.