Correct Option
The correct option is (c).
Explanation
The atmosphere is a layer of gases surrounding the Earth, held in place by gravity. Atmospheric pressure is defined as the force exerted by the weight of the air column at a given point. This pressure is dynamic and varies based on altitude, temperature, and Earth's rotation.
Statement-wise Analysis
- Statement 1 is Correct: The atmosphere has mass, and due to the Earth's gravitational pull, it exerts weight on the surface. This weight constitutes atmospheric pressure.
- Statement 2 is Incorrect: Atmospheric pressure is not uniform across the Earth's surface. It varies vertically (decreasing with altitude) and horizontally (due to differential heating of the Earth's surface and the rotation of the Earth).
- Statement 3 is Correct: Air naturally flows from areas of high pressure to areas of low pressure to equalize the difference. This horizontal movement of air is known as wind.
Key Takeaway
Atmospheric pressure is the weight of the air column, which varies across the Earth's surface; these pressure differences create the pressure gradient force that drives wind from high to low pressure.