# Motion Graphs

These pages were conceived as aids to teaching about position-time graphs and velocty time-graphs, particularly when presenting in front of a group with a projected screen or interactive whiteboard, or in a remote teaching situation by sharing the screen.

##### Basic Page

• The ball moving with a constant velocity.
• The ball speeding up.
• The ball slowing down.

Use the buttons on the bottom row to select between the three motions, and the play button to start the motion.  The animation will stop automativcally when the ball runs off the edge of the screen.  You must use the reset button after each run.  The animation can also be paused/resumed or reset while it is running.  Other controls are not available while the animation is running.

You can write/draw over the graphs and ball with touch/mouse.  This could be useful for illustrative or explanatory purposes.  The "x" button will clear all annotations.

The ball "track" is divided into 20 divisions.  Numbers on the graph correspond to these divisions, e.g. a position of +6 units corresponds to 6 divisions in from the left edge of the track (the reference point).  Similarly, a velocity of +4 units corresponds to the ball moving 4 divisions to the right every second.  It might be convenient to think of these divisions as "metres".

##### Custom Page

This page is similar to the Basic page, but allows for more customization.

The buttons on the 2nd row can be used to change the position of the reference point (marked by a thicker magenta line on the track), and the starting position of the ball.  Use the sliders to adjust the initial velocity and the acceleration of the ball.

Possible uses include:

• Exploring the effect of changing velocities or accelerations on the shape of the graphs.
• Exploring how shifting the relative positions of the reference point and ball affect the graphs.
• Predict graph shapes given an initial velocity and an accelration, then run the animation to check.

The animation runs for 10 seconds, even if the ball or graph lines go off the screen during that time.  As with the Basic page, the animation can be paused/resumed or reset at any time.  Other controls are disabled while the animation is running.

As with the Basic page, numbers on the graphs correspond to the divisions on the ball track, and you can write over the top of the graph and track with touch/mouse if desired.