We are now going use the JAVA applet "SimPhysics" below to find the causes of the motion of the puck you observed in Exercise 2. First open the applet by clicking on button below. It will open the applet in a new window. You can click on the white map area to change the field point or you can hold down the mouse button and drag the arrow around to explore the field. Notice that the applet has added some new selections to the menu.
1) Bring up the Fields Equations box by making sure the SimPhysics window is in the foreground and go to the Fields menu and select "Field Equations".
2) You may have to resize the SimPhysics window so that you can see both SimPhysics and the Field Equations at the same time. If you click on other windows the SimPhysics and Field Equations windows will move back and you will have to click on them to bring both to the fore.
1. Find two places where the magnitude of the electric field is 0.3. What do these places have in common?
2. How many places can you find where the electric field has only a y component? ...only a x component? What characterizes these places?
3. How many places can you find where the electric field makes a 45 degree angle up from the positive x direction?
4. How many places can you find where the electric field is zero?
5. In what direction does the electric field point between the two charges? How is this direction related to the direction of the deflection of you puck for exercise four?
6. Now choose "Show Vector Graph" from the Camera menu. Review you answers to questions 1-5.
7. Choose "Hide Vector Graph" from the Camera menu. Choose "Show Plot" from the Camera menu. The color mix (RGB value) is determined by the relative strength of the field from each charge.
8. Choose "Use Color Strength Plot" from the Camera menu. How does this plot differ from the plot in question 7?