Classroom Questions

Questions for ‘How to make a pitched ball curve to your will’

a still image of a baseball flying through the air towards a batter

In baseball (here), softball and cricket, a good pitch moves differently than the batter expects, either in the ball’s speed or its path. This makes it difficult to hit. Pitchers have various tricks for changing a ball’s flight path.

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By Science News Explores

To accompany ‘How to make a pitched ball curve to your will’

SCIENCE

Before Reading:

  1. A curveball is a type of baseball pitch. To the best of your understanding, explain what sets a curveball apart from a typical pitch. If you are not sure, speculate based on the name.
  2. Consider your description of a curveball above. How do you think a pitcher might throw a curveball? Consider two factors, such as the type of throw or some physical characteristic of the baseball, that could contribute to a curveball. (Feel free to be creative. You don’t have to answer correctly. The point is to consider how different factors might influence how a ball moves.)

During Reading:

  1. Explain what is meant by a baseball’s “spin.”
  2. State Isaac Newton’s Third Law. 
  3. What force does the Magnus effect create?
  4. For a ball pitched with a topspin, which direction will the wake move?
  5. Explain how a pitcher uses spin to counteract gravity when throwing a fastball.
  6. Besides mechanical engineering, what is Bart Smith’s second area of engineering expertise?
  7. Smith describes “boundary layers” that form around a pitched baseball. What do these layers consist of? 
  8. Contrast the spin of a fastball with a knuckleball.
  9. Contrast the stitch pattern of a cricket ball with that of a baseball.
  10.  What does it mean to say that a ball’s boundary layer is “laminar”?

After Reading:

  1. Attempt to pitch a ball, such as a baseball, gently. To what extent were you successful? Next, attempt to throw a ball with a topspin. Was this attempt more successful, less successful or about the same level of difficulty? Imagine someone offered you $1 million if you could master one type of pitch from this story. Which would you choose? Explain your answer.
  2. What does this story mean when it says that fastballs actually “have a hidden curve”?
  3. Pick one other type of pitch besides those described in this story, such as a slider or sweeper. If you’re unsure what this kind of pitch looks like, try a quick internet search. Briefly describe this type of ball movement. To what extent do you think the Magnus effect influences this type of ball movement? Explain your answer.