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As part of their training, NASA astronauts are placed in large rotating machines to see how well their bodies can withstand various “g” forces. (One g equals the gravitational force of gravity at the earth’s surface.) (a) What rotational speed is needed in a device with radius 6.25 m to allow a 75.8-kg astronaut to experience a force that is twice his normal weight or “2 g”? (b) What rotational speed is needed to achieve a “4 g” effect? (c) Would the rotational speeds found in (a) and (b) change if the astronaut had a different mass?
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