Physics: Pressure & Fluids

Question 1

Pressure

Answer 1

Pressure = Force/ Area

Question 2

Absolute Pressure

Answer 2

Absolute Pressure= Gauge Pressure + Atmospheric Pressure

Question 3

Hagen-Poiseuille Equation- Laminar Flow

Answer 3

Flow (Q) = π^Pr⁴/ 8nl

^P= Pressure drop along the tube

r= Radius

n= Viscosity

l= length of tube

Question 4

Reynold’s Number

Answer 4

= pvd/ n

p= density

v= velocity

d= diameter of the tube

n= visocisity

Dimensionless number < 2000 likely laminar >2000 like turbulent flow

Question 5

Turbulent Flow

Answer 5

Is proportional to…

vP= square root of pressure drop

Is inversely proportional to…

vl= square root of the length of the tube

vd= square root of the density of fluid

Question 6

Bernoulli’s Equation

Answer 6

½ pv² + P = K

K= constant

P= Potential energy

p= density

v= velocity