Fred carried a 100 N basket to his apartment the fifteenth floor of his building by climbing the stairs
June used a pulley hung from a fifteenth floor window that amplified her force by a factor of 3 to raise a different 100 N basket up to the apartment. Fred claims he'd done more work. June disagreed and says she'd put out more power. Is either person correct? Explain.
Neglecting friction in the pulley, Fred and June have done the same amount of
work to lift the baskets. June had to pull three times as long a rope as the 15 stories,
exerting a smaller force through a greater distance. If friction is included, then June will
have to have done more work than Fred.
Power is work done divided by the time required to do the work. We cannot address the
power question because we have no idea of the amount of time that Fred and June took.
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