Question

Two people who weigh the same climb a flight of stairs. Thefirst person climbs the stairs in 30s., while the second person climbs them in 40s. Which person does more work? Which uses more power?

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asked 2021-03-09
Two people who weigh the same climb a flight of stairs. Thefirst person climbs the stairs in 30s., while the second person climbs them in 40s. Which person does more work? Which uses more power?

Answers (1)

2021-03-10
Both do the same work, they do NOT use the same power.
Work is just force times distance, in this case the force(against gravity) equal to their weight.
Power is work per time: P=W/t
Since the first person climbs the stairs in a shorter period of time, he (or she) uses more power.
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