A particle of charge = +5.5 µC is released from rest at the point x = 55 cm on an x axis. The particle begins to move due to the presence of a charge Q that remains fixed at the origin.
(a) What is the kinetic energy of the particle at the instant it has moved 40 cm if Q = +15 µC?
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(b) What if Q = -15 µC?
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