Fluids Fluid statics Density and Pressure M Density
- Slides: 8
Fluids Fluid statics: Density and Pressure
M Density V Density is calculated the same way for solids, liquids, and gases. n Density = Mass / Volume n Liquids and gasses collectively are called fluids. n
Pressure vs. Force F P A Mini-lab - hang the 500 g mass from your finger, then repeat with a penny under the hook! n Pressure is defined as the force per unit area. Pressure = Force/Area n Equal forces can have unequal effects, depending on the pressure involved. n – Sitting on a bed of nails vs. A single nail – Someone standing on your hand in tennis shoes vs. A stilleto heel
Pressure of Fluids The unit for pressure is the same for solids and fluids - N/m 2 or Pascals (Pa) - 1 N/m 2 = 1 Pa n The force exerted by a fluid at rest on any rigid surface is always perpendicular to that surface. n
Pressure of Fluids The pressure of a fluid depends on the depth of the fluid, not on the total amount of fluid or the size or shape of the container. n So fluid pressure = density x gravity x height (depth of fluid), P = gh n
Hydrostatic Pressure is the pressure exerted on a surface by a column of fluid. n It depends on both the original atmospheric pressure pushing on the surface of the fluid AND on the fluid density and depth of the water beneath the surface of the fluid. n
Hydrostatic Pressure n Hydrostatic Pressure = Atmospheric pressure + density x acceleration due to gravity x depth Ph = Pa + gh n 1 Atm. STP = 1. 01 x 105 Pa or 101 k. Pa n
Additional Practice n Video - ESPN Sports. Figures : Math Under Pressure n Worksheet 9 -1 on Density & Pressure
