Understanding Graphs of Motion: Giving Qualitative Descriptions

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Free Fall Physics Practice Problems

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:01 No Math Today
  • 0:26 Qualitative Graphing
  • 1:45 Basic Graph Shapes
  • 4:52 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed Audio mode

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Angela Hartsock

Angela has taught college Microbiology and has a doctoral degree in Microbiology.

You can just look at graphs of straight line motion and accurately describe how that object is moving. In this lesson, we will investigate the basic shapes the graphs can take and what conclusions you can draw from these shapes.

No Math Today

For some of you out there, I have some good news. This kinematics lesson will not include any numbers or math. At this point, you should know how to perform all the necessary calculations with Position vs. Time and Velocity vs. Time graphs. Now, we're going to see what we can figure out just by looking at the shapes of these graphs, no numbers required.

Qualitative Graphing

If I show you two different Position vs. Time graphs and ask you to tell me which one represents an object traveling at a constant velocity, you should have no problem figuring it out.


After all, this graph shows the position and the time both changing at a constant rate. The second graph shows an object that is not moving. If you had to, you could calculate the slopes of the graphs and give me the velocity. But, what if I take away all the numbers? Can you still pick out the graph of constant velocity? Of course you can. The graph still shows the position and time changing at a consistent rate even though I've taken away the actual values.

What you've just done is make a qualitative assessment of the graph and used it to describe the motion of the object. With qualitative graphing you are describing the motion of an object by recognizing the basic shapes on its graph, not through exact calculations.

The best way to proceed is to look at the seven basic shapes of Velocity vs. Time and Position vs. Time graphs. By the end, you should be able to quickly recognize what's going on in each graph, what a specific type of motion looks like on both types of graphs, and how to sketch one type of graph if given the other type. Let's dive right in.

Basic Graph Shapes

Here's #1.

1: The object is not moving.


As you can see, the position is not changing on the first graph, and the velocity is 0 m/s on the second. Here, you are simply standing still.

2: The object is moving at a constant velocity in the positive direction.


Here, position and time are changing at a constant rate, upwards. The velocity graph is horizontal, above the time axis. Now, you are walking a steady pace forward.

3: The object is moving at a constant velocity in the negative direction.


These graphs are the opposite of #2. Position is constantly changing downward. Velocity is a horizontal line below the time axis. Back at the starting point, you decide to walk backwards at a steady pace.

4: The object is speeding up (or accelerating) in the positive direction.


The Position vs. Time graph shows an object that is moving faster as time passes, drawn as a curve. The velocity graph is increasing constantly, in a straight line. A steady speed won't cut it anymore. You start walking slowly but steadily move faster until you're running forward.

5: The object is slowing down in the positive direction.


To unlock this lesson you must be a Study.com Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use Study.com

Become a Study.com member and start learning now.
Become a Member  Back
What teachers are saying about Study.com
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account