1. Now let’s create a scatterplot of these data!
Go ahead and open up the “Braking Distance” Excel spreadsheet.
Take a few moments to insert the braking distances on both dry and icy pavement.
Now let’s create a scatterplot of these data!
(A “scatterplot” is a graph
that allows you to see the
interplay between
the two variables)
What pattern appears to exist between breaking distances and speed?

2. Linear Models have a constant slope… y = mx + b
Quadratic Models have a constant acceleration!
y = ax2 + bx + c
Notes!
While the units of slope are intuitive…rise unit/run unit, the units of acceleration are
not immediately so… rise unit/(run unit)2.
In a “perfect” quadratic model, with an object starting from rest, b and c should
be zero.
First (slope) versus second (acceleration) differences!
Let’s go outside!