# Define pressure. State its SI and CGS units and dimensions.

1.1k views
in Physics
closed

Define pressure. State its SI and CGS units and dimensions.

+1 vote
by (33.9k points)
selected

Definition : The pressure at a point in a fluid in hydrostatic equilibrium is defined as the normal force per unit area exerted by the fluid on a surface of infinitesimal area containing the point.

Thus, the pressure, p = limΔA→0 $\frac{F}{ΔA}$ where F is the magnitude of the normal force on a surface of area ∆A. The pressure is defined to be a scalar quantity.

SI unit: the pascal (Pa), 1 Pa = 1 N∙m-2 CGS unit: the dyne per square centimetre (dyn/cm2)

Dimensions : [p] = [F][A-1] = [MLT-2 , L-2] = [ML-1T-2]