What is considered a small velocity?

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The discussion revolves around the ambiguity of defining a "small velocity" in physics problems, particularly in the context of an elevator being pulled upwards. Participants express frustration over the lack of specific velocity values, which complicates problem-solving. Suggestions include using average elevator speeds or arbitrary small values like 0.01 m/s as assumptions. The conversation highlights a broader issue in physics where multiple assumptions are often necessary to arrive at a solution, contrasting it with more straightforward mathematical problems. Ultimately, the challenge lies in navigating these assumptions to find a workable answer.
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Homework Statement



An elevator is being pulled upwards with an small inital velocity. The elevator cable has a constant tension. After 250 seconds it stops with a gravitational energy of 2400J. Assume the acceleration due to gravity is 10. What is the mass of the elevator?

Homework Equations



PE=mgh

The Attempt at a Solution



Assume what v is then see how high it is then plug into find m.
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Anyway, when a problem says that something is traveling at a small velocity, but does not state what velocity to use, what should we take it as.

This is actually what I don't like about physics. In math if I am given an integral to solve I don't assume anything, I just do it.

I remember in thermodynamics, there was this one problem about a turbine and I tried very very hard to solve it without looking at the solutions manual. Then finally I gave up and looked at the manual and guess what. There was like 3 different assumptions you had to make an order to solve it. Thanks a lot physics.
 
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Maybe try looking up the average speed of an elevator and take half of that ... or just go with .01 m/s.
 

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