Homework set - 3
due on Wednesday, September 25, 11:00am
1) Problem 2.4 from Fetter and Walecka
2) Problem 2.5 from Fetter and Walecka
3) Problem 2.1 a) from Fetter and Walecka
b) What is the trajectory of the particle with charge e in the rotating frame
you found in part a?
c) Assume that B is perpendicular to the plane in which the charge e would
move if B = 0. What is the trajectory in the inertial frame with the same
origin as the rotating frame?
4) next page
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4) Imagine a long straight wire rotating in free space with constant angular
velocity ! about a perpendicular axis through its midpoint O. This axis is
fixed in inertial space. A bead of mass m slides on the wire. The coefficient
of kinetic friction between the bead and the wire is µ. The bead is initially a
distance x0 from O and moving with speed v0 along the wire. Calculate its
position x(t) on the wire in terms of !, µ, x0 and v0. Is there some value of
v0 for which the motion is bounded? Discuss the trajectory x(t).
In the rotating reference frame the problem is one-dimensional.
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