2. ELECTRIC FIELD SUMMARY 1/26/10 STUDIO

3. What’s up?  Reading Assignment – Read all of chapter 18. We will try to finish all of it (Gauss’s Law) by Friday.  There will be another quiz on Friday covering through today only.  The next chapter will be on Potential and Capacitors.  The first exam will follow the conclusion of chapter 19.

4. Electric Field

5. The Math

6. A small spherical insulator of mass 4.20 10 -2 kg and charge +0.600 µC is hung by a thin wire of negligible mass. A charge of −0.900 µC is held 0.150 m away from the sphere and directly to the right of it, so the wire makes an angle θ with the vertical.

7. A tiny ball of mass m carries a charge of +Q. What electric field (magnitude and direction) is needed to cause the ball to float above the ground? Q mg QE

8. The Map C Strong Weak The map gives the DIRECTION of E.

9. Field Lines begin and terminate on charges. In this case, the terminating charges are at “infinity”.

10. We will study this in the next chapter

11. Back to Work!