Why we are not crushed under the large atmospheric pressure?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4.
Answer: Because the pressure inside our body balances the outside pressure
Detailed Explanation:
- Surrounding us is a vast envelope of air known as the atmosphere. This air exerts a significant amount of pressure on us at all times, which is referred to as Atmospheric Pressure.
- We are not crushed by this pressure because:
- Internal Pressure: The fluids (such as blood) and cells present inside our bodies exert an equal amount of pressure outwards.
- Balance: This internal pressure is equal to the external atmospheric pressure, causing the two to balance (or cancel out) each other.
Key Points:
- At sea level, the average atmospheric pressure is approximately 101.325 kPa (kilopascals).
- As we ascend to higher altitudes (such as on mountains), the atmospheric pressure begins to decrease. This is why nosebleeds sometimes occur at high altitudes, as the body's internal blood pressure exceeds the external pressure.
Analysis of Other Options:
Option 1: The body's structural strength is derived from its bones; however, this alone is not sufficient to withstand the pressure of the air.
Option 2: Gravity pulls the air towards the Earth, thereby creating pressure; it does not protect us from this pressure.
Option 3: Atmospheric pressure is, in fact, very high (roughly equivalent to the weight of an elephant resting on our heads); therefore, this option is incorrect.