When it comes to rural roads, there’s a big difference between pavement and gravel. Especially when it comes to stopping distances. A cool website can help teachers demonstrate the difference to their students.
Forensic Dynamics offers an online calculator. Students select the road condition and speed traveled. The site will determine how many feet is needed to stop based on the selections.
It also offers the ability to determine the speed traveled based on the length of a skid, but aside from investigating an accident, I’m not sure who would want or need that information.
Have kids play around with the calculator. Encourage them to select various road conditions and speeds to see the difference it makes on the length of space needed to stop.
Just don’t forget to change the units of measure to miles per hour and feet.
They could turn the information into a graph or use the information for math problems for older kids.
For example, if you’re traveling at 55 mph and how many seconds will it take to travel the 144.56 feet it takes to stop? Ask them to consider how that time would be impacted considering the car doesn’t maintain 55 mph through the stop.