Pressure

Question 1

What is atmospheric pressure?

Answer 1

Atmospheric pressure is the force per unit area exerted by the weight of the atmosphere above a surface.

Question 2

What are the S.I units of pressure?

Answer 2

The S.I unit of pressure is the Pascal (Pa), where 1 Pa = 1 N/m².

Question 3

What are some instruments used to measure pressure?

Answer 3

Pressure can be measured using instruments such as a mercury barometer, aneroid barometer, and a manometer.

Question 4

How does pressure vary with height?

Answer 4

Pressure decreases with an increase in height due to the reduction in the weight of the air column above.

Question 5

Q: What is the relationship between pressure, depth, and density in a liquid?

Answer 5

A: The pressure 𝑃 in a liquid is given by 𝑃 = 𝜌𝑔ℎ
where 𝜌 is the density of the liquid,
𝑔 is the acceleration due to gravity,
and ℎ is the depth.

Question 6

What is Pascal’s Principle?

Answer 6

Pascal’s Principle states that pressure applied to a confined fluid is transmitted equally in all directions throughout the fluid.

Question 7

What are some applications of Pascal’s Principle?

Answer 7

Pascal’s Principle is applied in hydraulic systems, such as car brakes and hydraulic presses, where a small force applied at one point is transmitted to create a larger force at another point.

Question 8

How can you recognize the S.I unit of pressure?

Answer 8

The S.I unit of pressure is the Pascal (Pa), which can be derived from the formula ** 𝑃 = 𝐹 / 𝐴 **
where 𝐹 is force in newtons (N) and 𝐴 is area in square meters (m²).

Question 9

Q: What is the relationship between pressure, depth, and density?

Answer 9

A: Pressure in a liquid increases with depth and density, following the formula
𝑃 = 𝜌𝑔ℎ