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I(25 points). Multiple Choice:  Circle the most correct answer and mark
the answer on the bubble sheet.

(4pts) Which
of the following is NOT one of Maxwells equations?

(4pts)An electron enters
a spectrometer with a kinetic energy of 1.6x10-16
J.  What is the direction from its entry point that the electron
deflects?

electron

Detectors                B

a) left

b) right

c) into page

d) out of page           v

e) does not deflect

(4pts) From 2) if B=1.2T what is the distance from its entry point
that the electron collides with the detector (reverses direction) in
mm?

a) 0.122

b) 0.178

c) 1.123

d) 1.177

e) 1.442

(4pts) A circular
ring with 20 turns sits in a magnetic field that changes with time,
B=1.2t T/s, with the direction shown below, and has a radius R=1.3cm. 
What is the direction of the current induced in the loop? (At t=0, B=0).

a) clockwise               B X X X X X 

b) counter-clockwise

c) no current            X    
X     X     X 

d) not enough information

X X X X X 

(4pts) From 4), If the resistance in the loop is 23ohms, what is the
magnitude of the current in micro Amperes?

a) 120

b) 230

c) 340

d) 550

e) 730

6) (5 pts) Amperes law
relates:

a) changing B fields to E fields

b) magnetic fluxes to currents

c) electric fluxes to charge densities

d) currents to magnetic fields

Written Solutions: Show your work and explain reasoning.

III. (30pts)  Rotating Rod in a Magnetic Field              X        B X  
 X X X        
A conducting rod of length L is fixed at one end and is  

rotating in a uniform magnetic field, B, directed into the

page, with a constant angular speed .  Assume it has just

started rotating and no charges have built up.   X X  
 X X 

      v

a)  Indicate on the picture at right the direction
of the current   

induced in the rod, I.     X X    X  
 X X

b)  Indicate the direction
of the force from the magnetic field

on the rod from the induced current, and label it F<sub>ind.

c)  Explain the reasoning
you used to get the answers to parts a) and b).  Be sure to list
clearly all relevant laws and principles

d)  Find the rate
of area swept out by the rod with time, , as a function of , L,
and other relevant constants.[Hint: you dont necessarily need to take
a derivative]

e)  Find the induced
EMF across the rod as a function of , L, B, and other relevant
constants.