fluid mechanics - drag

Question 1

what is fluid mechanics

Answer 1

the study of fluids (gases and liquids) in a static or dynamic state

Question 2

what is fluid dynamics

Answer 2

the study of forces on fluids

Question 3

what fluid forces do we need to know

Answer 3

drag
lift

Question 4

what is a drag force

Answer 4

a resistance force which flows a body or object down
acts in the opposite direction to movement

Question 5

state and explain two types of drag

Answer 5

surface drag
-caused by friction when fluuid movement passes over the surface of an object or body

form drag
-how the size and shape of an object/body can affect how air passes over it
-factors that affect the LEADING EDGE increase drag, factors that affect the TRAILING EDGE reduce drag
-altering a body/object so that it passes through the air/water more efficiently is called STREAMLINIING

Question 6

examples of surface drag

Answer 6

swimming caps
thin paint on a bike
shine finish on ski suits

Question 7

examples of form drag

Answer 7

body position when skiing or cycling (creating a smaller leading edge)
size of bike wheels/fork

Question 8

what is ‘drafting’ in cycling

Answer 8

a large form drag also offers less turbulant air for anything that follows
-this is celled a slipstream

30cm=30%

Question 9

factors that increase and reduce drag

Answer 9

1. the velocity of the moving object
2. the cross sectional area of the moving object
3. the shape and surface charactoristics of the moving object