Press the play button. Watch the graphs to see the motion of the spring pendulum. Can you distinguish the pattern of spring motion (up and down) from the pattern of pendulum motion (back and forth)? How are the two related? Is there a regular pattern to the motion? Compare the periods of the two graphs. How many different patterns can you produce by changing the variables – gravity, rod length, mass and spring constant? Under what conditions does the energy switch between back and forth and up and down? Does the initial starting angle affect the patterns when all the other variables are unchanged?