Assume all the electrons in 21 gram of copper atoms were placed at the North Pole of the earth and all the protons at the South Pole. The radius of the Earth is 6370 kilometer. Take the mass number of copper to be 64.
(a) Obtain how many electrons are in 21 grams of copper?
(b) Find what would be the magnitude of the total force of attraction exerted on each group of charges by the other?
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(c) Find what would be the magnitude and direction of the force exerted by the charges at the Poles on a third charge that is equal to the charge at the South Pole, and located at a point of the surface of the Earth at the equator?
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