How Fast Can You Throw A Baseball?

 

These children are using a radar gun to figure out how many miles per hour they can throw a baseball.
 

• Find out how many miles per hour you throw a baseball without using a radar gun.

 

These questions may be useful in helping students down the problem solving path:

• What information would be useful in figuring this out?
• What factors may affect your answer’s accuracy?
• How could two groups of people measuring the same pitch get different answers?

 

The direction I hope this challenge goes in is for students to determine how much time it takes a ball they throw to go a specific amount of distance by actually doing it.  For example, a group of three students could have a thrower, a catcher, and a time keeper.  The thrower stands X feet from the catcher.  The thrower throws the ball right when the time keeper yells “Throw!” and uses a stop watch to determine the Y seconds it is until the ball gets to the catcher.  The students will then have the throwing speed in X feet per Y seconds and will need to convert it to miles per hour.

Also note that answers for speed will likely vary greatly.  It will be a good opportunity to bring up conversations about measurement and calculation errors.  Some errors will be from them being unable to accurately time how long it takes the ball to travel from the thrower to the catcher.  Other errors will occur from mistakes made while doing the calculations.
 

• A stop watch
• Something to measure long distances with such as a measuring tape.

 

• CCSS 5.MD.1 – Convert among different-sized standard measurement units within a given measurement system (e.g., convert 5 cm to 0.05 m), and use these conversions in solving multi-step, real world problems.
• CCSS 6.RP.2 – Understand the concept of a unit rate a/b associated with a ratio a:b with b ≠ 0, and use rate language in the context of a ratio relationship. For example, “This recipe has a ratio of 3 cups of flour to 4 cups of sugar, so there is 3/4 cup of flour for each cup of sugar.” “We paid $75 for 15 hamburgers, which is a rate of $5 per hamburger.”