8.3 Viscosity, Adhesion, and Cohesion

1
8.3 Viscosity, Adhesion, and Cohesion

• Viscosity is the resistance of a fluid to flow.
• Some fluids flow more easily than others because
• Particles of different fluids have different
  shapes.
• Particles of some fluids are attracted to each
  other more strongly.

See pages 300 - 301
2
Viscosity, Adhesion, and Cohesion

• The flow rate is the speed at which a fluid flows
  from one point to another.
• The slower the flow rate the greater the
  viscosity.
• Oil has a larger viscosity than water, therefore
  oil has a slower flow rate.

3
The Effect of Temperature on Viscosity

• Temperature affects the viscosity of materials as
  follows
• Liquids
• Heated viscosity decreases
• Cooled viscosity increases
• Gases
• Heated viscosity increases
• Cooled viscosity decreases

Temperature effects how easily a liquid pours.
See page 302
4
Adhesion and Cohesion

• Adhesion and cohesion affect the flow rate of
  liquids.
• Adhesion is the attraction of two different
  objects or fluids to each other.
• Cohesion is the strength with which the particles
  of an object or fluid attract each other.
• Surface tension is the property of a liquid in
  which the surface of the liquid acts as a thin
  skin due to cohesion.

The waters surface tension allows this insect to
remain supported.
See pages 304 - 305
Take the Section 8.3 Quiz