Concept explainers
Lucia's bathroom scale on the equator reads 110 lb when she stands on it. If her mass stays the same, will the scale read more or less at the North Pole? To answer this question, (a) draw a force diagram for Lucia. (b) With the assistance of this diagram, write an expression using Newton’s second law that relates the forces exerted on Lucia and her acceleration along the radial direction. (c) Decide whether the reading of the scale would be different at the North Pole List the - assumptions that you made and describe how your answer might change if those assumptions were not valid.
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