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Two point charges are moving as shown. The charges are equal in magnitude but opposite in sign. The velocities ofthe charges are equal. a. On the gure on your answer sheet, indicate the directions of the magnetic fields due to each charge at the mid-point between the charges. b. Derive an expression for the magnetic eld due to the negative charge felt by the positive charge. c. What direction is the magnetic force on the positive charge due to the negative charge? Explain. +. A