Fluid Mechanics
Factors that reduce and increase drag
Examples
Dynamic fluid force
Bernoulli's principle
Speed Skier
Cyclist
Race car
Discus
Drag and lift (two fluid forces)
Movement of liquids and gases
Drag force:
Form Drag
Surface Drag
Skin drag
Swimmers shave body hair to reduce surface drag
Relates to friction between surface of an object and it's fluid environment
shape drag
Relates to stream lining
Impact of a fluid on an object
Cross sectional area of the moving body
Shape and surface characteristics
Velocity of moving body
Increased velocity = increased drag force
can reduce and increase drag
Larger area = Increased drag
Less streamlined= more drag and greater effect of air resistance
More streamlined= Less drag
smaller area = reduced drag
Negative lift force = (Down force)
Describes how an upward lift force is created
distribution of air pressure can cause an upward or downward force
faster the air moves= less pressure
Pressure gradient high to low
distance of air travelled has an impact as well further distance means faster travelling