Module 4: Foundations of Trigonometry

 

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In Discover you saw that each counterclockwise rotation of the terminal arm increases the angle measurement by 2π, or 360°. For each clockwise rotation of the terminal arm, the angle measurement decreases by 2π, or 360°. In Try This 2 you will apply this understanding to determine the distance travelled by a horse.

 

Try This 2

 

Sometimes a horse walker is used for horses that need rehabilitation. The horses are tied to a pole at the centre, and they walk at a constant rate around the circular horse walker.

 

This is a graphic of four horses inside a circular fence walking around a circle. Each horse is tied with a rope to a centre post.

 

A horse walker has a radius of 6 m. The horses take 12 s to walk 1 revolution.

  1. What distance does a horse walk after 1 revolution? Place this information in a table similar to the one shown.
  2. What distance, and through what central angle, will the white horse travel after the times specified in the table?
  3. Complete the rest of the table.

      12 s 24 s 36 s
    Number of Revolutions 1    
    Distance Travelled by White Horse to the Nearest Tenth of a Metre 37.7    
    Diagram of Rotational Angle in Standard Position This is a sketch of a 360-degree angle drawn in standard position.    
    Angle of Rotation in Degrees 360°    
    Angle of Rotation in Radians 2π    
  4. How did you determine the distance travelled by the horse? Explain your process.

  5. Explain how you found the rotational angle.
  6. How do the terminal arms for each revolution compare?

course folder Save your responses in your course folder.

The distance around 1 revolution is equal to the circumference of the horse walker.