Fluid Mechanics

Question 1

Fluid mechanics

Answer 1

study of forces acting on a body when travelling through the air or water

Question 2

Air resistance

Answer 2

acts on a body travelling at high velocity through the air ( cyclist or sprinter)

Question 3

Drag

Answer 3

acts on a body travelling through water

Question 4

Air resistance and drag

Answer 4

act in opposition to the direction of motion of the moving body and must be minimised.

Question 5

Factors affecting the magnitude of air resistance and drag on the body

Answer 5

1) Velocity
- greater the velocity the greater air resistance or drag (speed skating, freestyle swimming)

Question 6

2) Frontal cross sectional area

Answer 6

larger the frontal cross sectional area the leader air resistance or drag (track cycling or downhill skiing)

Question 7

3) Streamlining and shape

Answer 7

more streamlined or aerodynamic the shape of the bday in motion, the lower the air resistance or drag.

Question 8

Streamlining

Answer 8

creation of a smooth air flow around an aerodynamic shape

Question 9

4) Surface characteristics

Answer 9

the smoother the surface the lower air resistance or drag.
- sprinters speed skaters skiers wear specially engineered clothing to create the smoothest surface possible to reduce the friction between the fluid and body surface.

Question 10

How to reduce drag - Skiing

Answer 10

• low crouched position to minimise cross sectional area.
• wear teardrop shaped helmets and have find on their gloves and boots to create a streamlined shape easing the airflow.
• super silky lycra suits to create a smooth surface for air to pass over

Question 11

How to reduce drag - cycling

Answer 11

• lightweight carbon bike design helps with aerodynamic features such as disc wheels and aerodynamic forks to reduce energy expenditure and minimise air resistance.
• aerodynamic riding position with shoulders forward, high seat position to tilt the body forwards and narrow handlebars.
• aerodynamic glossy helmets