Concept explainers
You are working as an expert witness for an inventor. The inventor devised a system that allows an 85.0-kg human to hover above the ground at the surface of the Earth due to the repulsive force between a charge q applied to his body and the normal electric charge on the Earth. The normal charge on the Earth is such that the electric field is uniform from near the Earth’s surface, directed downward toward the surface, and is of magnitude 130 N/C at the location of the engineer’s experiments. Everything went well until the engineer tried a new experiment. He attempted to transfer the same amount of charge q to each of two experimental subjects standing next to each other, so they could hover and work close together on a task. The charged, hovering experimental subjects repelled each other and were injured as they flew away in opposite directions. Both experimental subjects are now suing the inventor for their injuries. The inventor is claiming that it is not his fault if the subjects find each other repulsive. To find out whether the inventor has a good defense, determine the initial acceleration of each subject if they are working 1.00 m apart.
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EBK PHYSICS FOR SCIENTISTS AND ENGINEER
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