PHY 2049: Physics II Tutoring Center is open in room NPB 1215, M-F 12:00AM -4:00PM. It is free. Hopefully all homework problems have been solved. Please see me immediately after the class if there is still an issue.

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.

PHY 2049: Physics II Force => work => change in K=> change in Potential energy ΔU = Uf – Ui = -W = - ΔK Work done is path independent. K+U = constant. U = k q1 q2/r

PHY 2049: Physics II Electric Potential Also 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 Vf –Vi = -∫E.ds Add as a number

PHY 2049: Physics II

PHY 2049: Physics II Rank them by the magnitude of electric field Which has the field pointed to the right What does an electron do when released midway

     PHY 2049: Physics II

PHY 2049: Physics II Vf-Vi = -∫ k q/r2 dr Choose Vi = V (∞)=0 V(r) = kq/r

PHY 2049: Physics II

Uniformly charged disk V = kpcosθ/r2 E = -∂V/∂s = - Uniformly charged disk V = ??

A B C (24 - 6)

. P r dq (24 - 7)

dq O A (24 - 8)

(24 - 9)

(24 - 10)

S A B  V q S V (24 - 11)

(24 - 12)

(24 - 13) A B V V+dV

(24 - 14) A B V V+dV

(24 - 15) x y O q1 q2 q3 r12 r23 r13

O x y  q1 Step 1 (24 - 16) x O r12 q1 q2  Step 2 Step 3 x y O r12

(24 - 17) path A B conductor

(24 - 18)

(24 - 19)

(24 - 20) R