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PROBLEM 1 - Electron in a Uniform Field
When the terminals of a battery are connected to two large parallel conducting plates, the
resulting charges on the plates cause an electric field in the region between the plates that
is nearly uniform (we will see the reason for this uniformity later). If the plates are
horizontal and separated by 1.00 cm and the plates are connected to a 100-volt battery,
the magnitude of the field is E=1.00*101\2N/C. Suppose the direction of E is vertically
upward, as shown in the diagram. a) If an electron is released from rest at the upper
plate, what is the acceleration? b) What speed and kinetic energy does it acquire while
traveling 1.0 cm to the lower plate? c) How much time is required for it to travel this
distance? An electron has a charge -e=-1.60*101\-19 C and a mass m=9.11*101\-31kg.
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PROBLEM 2 Field of Two Oppositely Charged Infinite Sheets
Two infinite plane sheets are placed parallel to each other, separated by a distance d (as
shown in the figure). The lower sheet has a unifonn positive surface charge density cr,
and the upper sheet has a unifonn negative surface charge density -(j with the same
magnitude. Find the electric field between the two sheets, above the upper sheet, and
below the sheet.
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