Question

Why does the nose start bleeding on high mountains?
A. Pressure inside body > atmospheric pressure
B. Pressure inside body < atmospheric pressure
C. Pressure inside body = atmospheric pressure
D. None of the above reason is correct

Answer 1

Hint:
- We can easily solve this question with the concept of effect of pressure on liquid movements.
- We know that atmospheric pressure decreases with high altitude. So, at higher altitude atmospheric pressure is lower compared to the pressure at the surface. At higher altitudes the blood pressure inside our body is more than the atmospheric pressure which forces the blood to ooze out from openings like the nose. Hence the nose bleeding.

Complete step-by-step answer:
We know that
Basically, the atmospheric pressure depends on the mass of layers of it as well as height from the surface of earth.
So, when we move upward from the earth surface the value of g, mass and density of atmospheric layers decreases as a result the atmospheric pressure decreases.
Because pressure can be defined as follow: -
${\text{P = }}\dfrac{{\text{F}}}{{\text{A}}}{\text{ = }}\dfrac{{{\text{mg}}}}{{\text{A}}}$
Where,
P=pressure
F= force
A= area
m= mass
g= acceleration due to gravity
So, when we move up to the mountains the atmospheric pressure decreases and a low pressure is created on our surrounding atmosphere.
But our blood pressure in veins remain constant which is most suitable on the surface of the earth
Now, a high pressure is created inside the body as compared to outer atmospheric pressure which creates a pressure difference inside our body and surrounding atmosphere.
As we know that the fluids start flowing from high pressure to low pressure therefore our blood starts flowing from the body through several openings of the body such as the nose.
Hence nose bleeding occurs because pressure inside the body > atmospheric pressure.
Therefore the correct answer is A.

Note: The low humidity dries the membranes of the nose, making them brittle and frequently causing nosebleeds. Dehydration and head colds may cause them as well. Avoid colds, stay hydrated and use a humidifier. If a nosebleed does occur, the most effective way to stop it is to pinch the nose together for 5 minutes.