Streamlining (Oxford AQA IGCSE Physics)

Streamlining

• The maximum velocity that an object travelling through a fluid can reach is its terminal velocity

• Terminal velocity is reached when the forward driving force (thrust) is equal to the drag forces

• Streamlining reduces the drag forces acting on an object, therefore increasing the maximum (terminal) velocity

Air resistance on a truck and a car

• In general, elongated, rounded shapes allow an object to pass through a fluid with minimal drag

• Racing cars are designed with streamlining features

Air passing over a racing car

• Splitter

  • Directs the airflow on top of the car with minimal drag

• Drive planes

  • Direct the airflow on top and around the sides of the car with minimal drag

• Side vents

  • Redirect air from the wheel wells to reduce turbulence

• Side skirts

  • Direct airflow along the sides of the car with minimal drag

• Wing & Spoiler

  • Directs airflow upwards to create a downward force on the car to increase stability

• Sharks have evolved to have streamlined adaptations

  • Sharks who can swim at faster speeds are better hunters

  • The most successful hunters are more likely to live long enough to reproduce and pass those adaptations on to their offspring

Adaptations of a shark

• Elongated, rounded body

  • Directs water flow around the body with minimal drag

• Pointed nose

  • Cuts through the water directing water flow around the body with minimal drag

• Smooth skin

  • Reduces friction of the water molecules on the skin