- #1
Rumplestiltskin
- 97
- 3
Homework Statement
A 55kW motor is used to lift a 4800kg mass vertically up a mine shaft. What is the maximum possible speed that the mass could move upwards? Give your answer to 2 significant figures.
Homework Equations
The Attempt at a Solution
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I correctly answered this as 55000 / (4800 * 9.8) = 1.2 m/s.
But first I went on a tangent rearranging KE = 0.5mv2 for v. Seemed like the most intuitive line of thought. Why was this mistaken? How would I avoid wasting time like that?