Aerodynamics

WASHINGTON NATIONALS

BASEBALL SCIENCE FUN SHEETS

OUT

SIDE ACTIVIT

Y

INTRODUCTIONWhat is the difference between a curveball, fastball and cutter? In this lesson, students will learn about the aerodynamic properties of a ball in flight and the influence of spin on its trajectory.

OBJECTIVES• Determine the trajectory of different pitches.• Simulate different types of pitches using a ball.• Explain why baseballs curve (Magnus Effect).

KEY CONCEPTS• Aerodynamics is about the way something

moves when passing through air. In this activity, students will measure the effect of changing the way a ball moves through air by where it ends up.

• Draw lines of symmetry of a ball.

• Plot the distance a ball curves from the center line.

MATERIALS• Worksheet

• Ball (beachball if available)

• Tape Measure

• Coins & Tape

KEY WORDS• Axis of Rotation

• Magnus Effect

• Curveball

• Fastball

FOCUS STANDARDS

Relates to Line of Symmetry:

CCSS.MATH.CONTENT.4.G.A.3

Relates to Coordinate Graphs:

CCSS.MATH.CONTENT.5.G.A.2

Aerodynamics

PROCEDURE

1. Show a Magnus Effect video to engage the students.

2. Provide students with paper and tape. Roll the paper to create a hollow cylinder.

3. On a tilted platform, release the roll of paper.

4. The rotation of the paper and Magnus Effect will cause the cylinder to spin as it falls towards the floor.

5. Draw a line of symmetry on the ball to understand the rotational axis (vertical vs. horizontal).

a. If a ball has top spin or backspin, it is rotating along its horizontal axis; if a ball has side spin, it is rotating

along its vertical axis.

b. The spin will be more exaggerated if a coin is taped to one side of the ball.

6. Students will try curving the ball by applying spin to it and observing its effect on the trajectory of the ball path.

7. Set up a line of tape about 30’ long. This will serve as the reference line.

8. Have students throw the ball parallel to the line.

9. The throw should deliberately apply spin to the ball to recreate the Magnus Effect.

a. The spin will be more exaggerated if a coin is taped to one side of the ball.

11. Measure how many inches the ball curves along the horizontal plane and record the results in the Worksheet.

12.The example provided shows two throws, the first throw curves four feet left and the second throw curves two feet right.

13.Observe how the ball curves along the horizontal axis by throwing a fastball (backspin) and a curveball (topspin).

14. Observe how the ball curves along the vertical axis by throwing a cutter (side spin).

15. After three trials of each of three different types of throws, these changes are plotted on a coordinate chart using zero as the center line and whole number positive and negative integers as measures for the curves.

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PROCEDURE

1. Show the Magnus Effect video

a. Provide students with paper and tape. Roll the paper to create a hollow cylinder.

b. b. On a tilted platform, release the roll of paper.

c. The rotation of the paper and Magnus Effect will cause the cylinder to spin as it falls towards the floor.

2. Draw a line of symmetry on the ball to understand the rotational axis (vertical vs. horizontal)

3. If a ball has top spin or backspin, it is rotating along its horizontal axis.

a. If a ball has side spin, it is rotating along its vertical axis.

b. The spin will be more exaggerated if a coin is taped to one side of the ball.

4. Students will try curving the beach ball by applying spin to it and observing its effect on the trajectory of the ball path.

a. Set up a line of tape about 30’ long. This will serve as the reference line.

b. Have students throw the beach ball parallel to the line.

c. The throw should deliberately apply spin to the beach ball to recreate the Magnus Effect. (The spin will be more exaggerated if a coin is taped to one side of the ball.)

d. Measure how many inches the beach ball curves along the horizontal plane and record the results in the Worksheet. (The example provided shows two throws, the first throw curves 4 feet left and the second throw curves 2 feet right.)

5. Observe how the beach ball curves along the horizontal axis by throwing a fastball (backspin) and a curveball (topspin)

6. Observe how the beach ball curves along the vertical axis by throwing a slider (side spin)

CURVEBALLFASTBALL SLIDER

Aerodynamics

ADDITIONAL SUPPORT

• Explore the concept of a line of symmetry by folding and marking an 8 ½ x 11 standard piece of paper

horizontally and then vertically. Both creases are lines of symmetry. Then try to fold it diagonally to notice

that mirror image sides are NOT created.

• Use a variety of objects to demonstrate rotational axis of spheres. (i.e., bead on a string)

• Support making accurate measurements by placing tape intervals with inches already marked on the tape

(negative and positive) on either side of the designated center line (or zero line) for the activity.

ONLINE RESOURCES

What Is The Magnus Force? (3:46) – https://tinyurl.com/ycmvgmwx – Engaging introduction and

demonstration of the Magnus Force that is behind how and why a thrown baseball will curve left or right,

sink, or move unpredictably.

How to Curve a Baseball (4:06) – https://tinyurl.com/y87x245d – A continuation from the previous video

that shows exactly how a ball, when modified with weights, shows the different movements a thrown ball

will make. Clear and informative for all levels.

Sports Balls Vs. Magnus Effect (5:17) – https://tinyurl.com/y9nfqo8u – A dramatic example of the Magnus

Force using an extreme ball drop with six different types of balls (baseball at 3:02 sec) at an outdoor venue.

POTENTIAL EXTENSIONS

Extension Idea #1 – From a safe and secure location, try to replicate the Magnus effect seen in the videos.

AerodynamicsWORKSHEET

STUDENT NAME

INSTRUCTIONS: Want to pitch like Max Scherzer? In groups, practice throwing a ball with

different spins to show how it affects trajectory. After each throw, measure the distance the ball

from the center line.

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STUDENT NAME:

Horizontal distance from center line (inches)

TOPSPIN

Throw #

1

2

3

Horizontal distance from center line (inches)

SIDESPIN

Throw #

1

2

3

Horizontal distance from center line (inches)

BACKSPIN

Throw #

1

2

3

-8 0

Center line

-6 2-4 4-2 6 8