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This is Giancoli Answers with Mr. Dychko. The electric field points in the same direction as the force it applies on a positive charge. Because this proton experiences a force towards the South, that means electric field must be to the South, because electric field points in the direction of force on a positive charge. The electric field strength is the force divided by the charge. That's gonna be 1.86 times 10 to the minus 14 Newtons divided by 1.602 times 10 to the minus 19 Coulombs, magnitude of a charge in a proton. This gives us 1.16 times 10 to the five Newtons per Coulomb electric field strength which is directed South.