Students will learn how to graph motion vs time. Specifically students will learn how to take the slope of a graph and relate that to the instantaneous velocity or acceleration for position or velocity graphs, respectively. Finally students will learn how to take the area of a velocity vs time graph in order to calculate the displacement.
Key Equations
For a graph of position vs. time. The slope is the rise over the run, where the rise is the displacement and the run is the time. thus,
Slope =
Note : Slope of the tangent line for a particular point in time = the instantaneous velocity
For a graph of velocity vs. time. The slope is the rise over the run, where the rise is the change in velocity and the run is the time. thus,
Slope =
Note : Slope of the tangent line for a particular point in time = the instantaneous acceleration
- One must first read a graph correctly. For example on a position vs. time graph (thus the position is graphed on the y-axis and the time on the x-axis) for a given a data point, go straight down from it to get the time and straight across to get the position.
- If there is constant acceleration the graph vs. produces a parabola. The slope of the vs. graph equals the instantaneous velocity. The slope of a vs. graph equals the acceleration.
- The slope of the graph vs. can be used to find acceleration; the area of the graph vs. can be used to find displacement. Welcome to calculus!