1. PHY 2049: Physics II Tutoring Center is open in room NPB 1100, M-F 10:00AM -3:00PM. It is free. Hopefully all webassign problems have been solved. Please see me immediately after the class if there is still an issue.

2. PHY 2049: Physics II About bicycle riding: If some one shows you a trick, it means that, It is possible to do that trick The person who showed you, can do the trick. It does not mean that you can do the trick. Try it a lot of times and you can too.

3. PHY 2049: Physics II Force => work => change in K=> change in Potential energy ΔU = U f – U i = -W = - ΔK Work done is path independent. K+U = constant. U = k q 1 q 2 /r

4. PHY 2049: Physics II Electric Potential V = U/q = -W/q Units of Joules/coulomb = volt 1 eV = e x 1V = 1.6 x 10 -19 J Also V = kq/r V f –V i = -∫E.ds Add as a number

5. PHY 2049: Physics II

6. Rank them by the magnitude of electric field Which has the field pointed to the right What does an electron do when released midway

7. PHY 2049: Physics II

8. PHY 2049: Physics II V f -V i = -∫ k q/r 2 dr Choose V i = V (∞)=0 V(r) = kq/r

9. PHY 2049: Physics II

10. V = kpcosθ/r 2 E = - ∂V/∂s = - Uniformly charged disk V = ??