Position and Velocity Graphs

Navigation Links

Fall 2009-Day 19
Force and Motion Activities

Today, the students got to explore motion more in depth. For each motion, the students drew a picture of what the graph would look like for position. Then, Emily set up a track in the middle of the room and rolled a basketball down it. She set a motion detector at the top of the track. She had the students try to explain what the graph would look like with both words and a picture based on what they already know about position graphs. The students found this to be a bit of a challenge, but with assistance from the instructors, they were able to correctly draw and describe the position graph for the motion they witnessed. Next, the students explored velocity graphs! They simultaneously watched the position graphs and the velocity graphs change during the same motion. By relating what they already knew about the position graphs, they were able to interpret what was happening with the velocity graphs. They broke each piece of the graph down, and explained what was happening. They discovered that velocity was measuring the speed of the motion. They found: If a change in position is constant, the velocity graph is a straight, flat line. If a change in position is gradual, the velocity graph is inclined. If there is no change in position, the velocity graph remains at zero. The steeper the position graph, the higher the flat line is on the velocity graph.

Drawing Position Graphs	Experiment, Watch, Learn	Position and Velocity Graphs
	The students re-created their initial motions, which were displayed on the position graphs. This time, the computer program was set up so both a position graph and a velocity graph were present. The students watched in amazement as they saw the connections between the two graphs.