1. Acceleration
Lesson 1C
Unit 1 Motion
Conceptual Physics

2. Learning Objectives
Describe and analyze motion in one dimension using equations with the concept of acceleration
In other words - How do you describe how an object is changing its velocity?

3. Terms
Acceleration

4. Acceleration
When the measured quantity is a change in velocity, the rate is called acceleration
Since velocity is a vector, acceleration is also a vector

5. Mathematically Acceleration is velocity change divided by time
Can be positive or negative depending on the sign of velocity (time interval is always positive)

6. Units
Acceleration is a ratio of velocity to time, so the magnitude units will be…
Examples include: m/s2, km/h2

7. Graphical Interpretation
Slope is ‘rise over run’ or the change in the y-axis value divided by the change in the x-axis value
On a velocity versus time graph, the slope is the change in velocity divided by the change in time, which is the definition of acceleration
So, acceleration is the slope of a velocity versus time graph

8. Instantaneous Velocity
Remember - velocity is the slope found on a position and time graph
When the line is straight, finding the slope is straight forward
When the line is not straight, then the instantaneous velocity can be found by the slope of a tangent line at the particular point in time