17.2.3. Factors Affecting Drag

Try these first

1. 1.

   Define drag in your own words.

   Hint

   Think about how a swimming fish experiences resistance in the water.

2. 2.

   What is the drag coefficient (Cd)?

   Hint

   Consider how a sports car might have a lower Cd than a van.

3. 3.

   What is the drag coefficient (Cd)?

   • A measure of lifting force
   • A dimensionless number for drag force
   • A measure of weight

   Hint

   Think about the role of shape in fluid dynamics.

4. 4.

   True or False: A rough surface increases drag.

   • True
   • False

   Hint

   Consider how water flows around different textures.

5. 5.

   A wind turbine blade has a length of 2 meters and a diameter of 0.3 meters. It operates in air that flows at a speed of 15 m/s. Calculate the drag force acting on the blade if the drag coefficient is known to be 1.5.

   Hint

   Ensure you account for the unit conversions if necessary.

6. 6.

   You are tasked to design a car with a minimized drag coefficient. What factors would you consider in your design process, and why?

   Hint

   Think about how racing cars are designed and what features they have compared to regular cars.