Lecture 28 - Fluid Dynamics Part 3

Question 1

lift force is generated … what to the flow

Answer 1

perpendicular to the flow, where as drag forces act in the direction of flow

Question 2

what is the equation of lift force

Answer 2

FL = 1/2 CLpAPVr^2

Question 3

what is Bernoulli’s principle

Answer 3

regions of relatively high velocity fluid flow are associated with regions of relative low pressure, and regions of relatively low velocity flow are associated with regions of relative high pressure

Question 4

what happens to the foil shape in the flow of a fluid (Bernoulli’s principle)

Answer 4

creates fluid separation with higher velocity-low pressure over the top and lower velocity - higher pressure over the bottom

Question 5

what is the angle of attack in terms of lift force

Answer 5

the angle of orientation of the projectile with respect to the fluid flow

Question 6

what is the optimum angle of attack for maximising range

Answer 6

the angle at which the lift/drag ratio is maximum

Question 7

spinning objects also generates

Answer 7

lift

Question 8

when an object in a fluid medium spins….

Answer 8

the boundary layer of fluid molecules adjacent to the object spin with i t

Question 9

what is the Magnus force

Answer 9

a lift force direction from the high pressure region to the low pressure region, created by pressure differential (created by spin)

Question 10

what is the usual orientation of a cricket ball in the conventional swing

Answer 10

use the seam, angled away from the intended direction of travel so the shinny side of the ball faces the batsman

Question 11

what is the usual orientation of a cricket ball in the reverse swing

Answer 11

when the seam is angled for the conventional swing but this time the rough side faces the batsman