Question

Bar of pressure is equal to:
A. 1 kPa
B. 10 kPa
C. 100 kPa
D. 1000 kPa

Answer 1

Hint: Bar is a metallic unit of pressure. But it is not an international system of units. One atmospheric pressure is equal to 1.01325 bar. 1kPa = 1000Pa using this basic thing we can solve the above problem.

Complete Step-by-Step solution:
Pressure is defined as a normal force exerted by a fluid per unit area.
Therefore $P=\dfrac{F}{A}$
Unit of F is Newton
unit of A is ${{m}^{2}}$
Pressure has a unit of newton per square meter which is called one Pascal.
1 Pascal = 1$\dfrac{N}{{{m}^{2}}}$
Bar= b
kilopascal = kPa
Bar = kilopascal
i.e. 1 bar = 100 kPa
Formula:
Kilopascal (kPa) = bar*100
Let’s take an example to understand more,
Example:
Bar = 2.5
kPa=?

kPa = bar* 100
       = 2.5*100
kilopascal = 250 kPa

Additional information:
Along with bar there is also a unit name psi (pounds per square) which measures pressure as a one-pound force applied on an area of one square inch whereas bar measures pressure as a force applied perpendicularly on a unit area of a surface. Especially psi measure terms related to pressure like stress, strain but bars measure only pressure.
1 atm = 760 torr = 101.3kPa = 14.7 psi
$\begin{align}
  & 1kPa={{10}^{3}}Pa={{10}^{3}}\dfrac{N}{{{m}^{2}}} \\
 & 1MPa={{10}^{6}}Pa={{10}^{6}}\dfrac{N}{{{m}^{2}}} \\
 & 1bar={{10}^{5}}Pa=0.1MPa=100kPa \\
 & \\
\end{align}$
Option C) is correct.

Note: The pressure units like bar, atm, and kgf/$c{{m}^{2}}$ are most equivalent units to each other. Clear the difference between bar and Pascal. Formula given in solution can be used to convert bar units into Pascal units. Bar and Pascal are usually used in physics and chemistry.