QUESTION

# The S.I unit of pressure is pascal?${\text{A}}{\text{.}}$ True ${\text{B}}{\text{.}}$ False

Hint- Here, we will proceed by defining the physical term pressure and then we will be writing the general formula used to determine pressure. Then, we will be discussing different units of pressure.

Pressure is defined as the physical force exerted on an object. The force applied is perpendicular to the surface of objects per unit area. It is also known as force per unit area.
The basic formula for pressure is given by
Pressure = $\dfrac{{{\text{Force}}}}{{{\text{Area}}}}$ i.e., P = $\dfrac{{\text{F}}}{{\text{A}}}$
The S.I unit of pressure is pascal or newton per square metre.
Other units of pressure are bar, gram-force and tonne-force (metric ton-force) per square centimetre, barye (dyne per square centimetre), etc.
Also, 1 bar = 100000 Pascal
There are basically four types of pressure which are absolute pressure, atmospheric pressure, differential pressure and gauge pressure.
The basic relationship between absolute pressure, atmospheric pressure and gauge pressure is given by
Absolute pressure = Gauge pressure + Atmospheric pressure
i.e., Absolute pressure at a particular point is the sum of the gauge pressure at that point and the atmospheric pressure at that point.
Therefore, the statement that the S.I unit of pressure is pascal is true.
Hence, option A is correct.

Note- Differential pressure refers to the difference between the pressures at two different points. The devices used for the purpose of pressure measurement are simple U-tube manometer (used to measure pressure at a point), inclined U-tube manometer (used to measure pressure at a point), differential manometer (used to measure differential pressure), etc.