Kinematic Graphing - Mission KG6 Detailed Help


The motion of an object is depicted by a velocity-time graph. Various time intervals during the motion are depicted by a letter. During which time interval(s) is the object moving with a constant velocity? List all that apply.



 
Velocity-Time Graphs:
Velocity versus time graphs represent changes that occur in an object's velocity with respect to time. The slope of the line is the acceleration (change in velocity divided by the change in time) of the object. The area under the line (between the line on the graph and the time axis) is the displacement of the object.


 
Many students confuse position-time graphs with velocity-time graphs. They know that a constant velocity on a position-time graph as a straight line. So they instantly begin looking for the same line on this graph. But don't be fooled! This is a velocity-time graph and the slope is the acceleration. A line with constant slope (straight diagonal) on a velocity-time graph is a line with a constant acceleration (meaning that there is a velocity change).


 
Many questions in this mission can be answered with a mixture of good math sense and logical thinking. The graph is a plot of velocity. Any motion that is characterized by a constant velocity would be represented by a line whose velocity coordinate is staying at the same level. Such a line is a horizontal line. A constant velocity motion is represented on a velocity-time graph by a horizontal line.