Using calculus, police investigate traffic accidents


Two tractor trailers and other vehicles were involved in an accident with injuries, utility pole and traffic signal destruction, and fuel spillage in East Lampeter Township, Pa., on Dec 4. (WGAL NBC News Channel 8, Lancaster via Flickr)

I’d be willing to bet that every math teacher in America has been asked, by more than a few students, When are we ever going to use this?

Given the wide range of possible directions their students’ lives may take, teachers often tap dance, wave their arms in the air, and squirt out a general answer that leaves their students completely unsatisfied.

But with a little help from community members, who are actually using math in their jobs, some teachers have found ways to answer the question and get students to learn some mathematics in the process of applying it in the real world.

Solving traffic accidents with calculus

A local police officer visited one South Dakota high school last month, explaining to students how math, particularly calculus, is often used as police investigate traffic accidents, The (Spearfish, S.D.) Black Hills Pioneer reports.

Using photographs and diagrams from local accidents, Officer Kale Nelson showed students in Chad Spear’s calculus class at Spearfish High School how mathematical formulas help police determine speed, angles, the drag factor on surfaces, and several other variables that are relevant to the investigation.

“The reason I like doing this is because when I was in high school and college, and I sat in math classes like you guys, I really didn’t care about it at all,” the paper quoted Officer Nelson as saying.

“Because, when am I going to use calculus, trigonometry, and geometry? Never. And then I get into this career and decide I like doing accidents … and use a lot of math.”

If a car left an asphalt roadway, crossed a dirt median, and then ramped up onto another asphalt roadway covered with brake fluid, how might you determine the minimum speed at which the vehicle was traveling before it initially skidded off the original roadway? See the Next Generation Science Standards for high school (forces and interactions), here, for more information.

About the Author

Paul Katula
Paul Katula is the executive editor of the Voxitatis Research Foundation, which publishes this blog. For more information, see the About page.