Question

How does blowing inside the bottle make the paper ball come out?
A. Air pressure near the mouth of the bottle rises and the reduced air pressure inside the bottle pushes the paper ball out.
B. air pressure drops inside the bottle and the air is pressed inside and the paper ball is pushed out.
C. Air pressure near the mouth of the bottle drops and greater air pressure inside the bottle pushes the paper ball out.
D. None of these.

Answer 1

Hint: A relationship between the speed of fluid and pressure was beautifully explained through Bernoulli’s principle. According to the principle, in fluids at a horizontal level, points, where the speed of the fluid is higher, will have less pressure compared to the point in the fluid at which lower speed. The fluid stands for both gases and liquid states.

Complete answer:
Let us see the condition mentioned in the question little scientifically. Consider a horizontally placed bottle. When we blow into it through our mouth the speed of air near the mouth of the bottle will increase and it will be greater than the speed of air inside the bottle internally. So as per Bernoulli's principle, the pressure of the air inside the bottle will be greater than the pressure near the mouth of the bottle.

When we try to put a crumpled paper ball into the bottle by blowing into the bottle. The internal high-pressure air will restrict the motion of the ball and create an interlocking situation between two pressures and as a result eventually the ball will come out of the bottle.
So, now here we can conclude that the correct answer which explains the behavior of the ball in this small experiment with a horizontal bottle.

So, the correct answer is “Option C”.

Note:
Bernoulli's principle is named after Sir Daniel Bernoulli who published this principle in his book "Hydrodynamica" in 1738. A better illustration of this principle was given by Leonhard Euler who derived Bernoulli’s equation in its usual form.