Fluid Mechanics

Fluid Friction

Aerodynamics

The forces that resists the movements of a solid object through a fluid

Related to the flow of air around a projectile, which can influence the speed and direction of the object

Hydrodynamics

Related to the flow of water around a projectile, which can influence the speed and direction of the object.

Air Resistance

It is a friction force, which occurs when air passes over the surface of objects . Drag force is a force acting opposite to the relative motion of any object moving with respect to surrounding fluid

How drag is affected?

Density of the Fluid

Cross Sectional Area of the object

Velocity of the Object

Shape of the object and how stremline it is

Streamlining

In activities where maximum speed is the aim, the drag must be minimised and this is achieved through streamlining

Bernoulli Effect

As Velocity of the fluid increases, the pressure extended by that fluid decreases. This leads to turbulence behind the object

Magnus Effect

BackSpin

Side Spin

Top Spin

Due to the air resistance formed at the top of the ball, the air is slowed down causing an area of high pressure above the ball

Due to the air resistance formed at the bottom of the ball,the air is slowed down causing an area of high pressure below the ball

In football, players use the Magnus effect to curve the flight path of the ball. The kicker places a side spin on the curling ball, curving it around the wall of the defensive players in goal.

Factors that Fluid Friction depend on:

Shape

Size

Speed

Streamlining

Examples

The Speedo LZR Racer Swimsuit

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Magnus Effect (Back Spin)

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