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spencer edward
Jan 8, 2009, 04:11 PM
The question asks about 782 N marine climbing a 12.2 rope in 6.58
And it asks what is the power output
And answer in W.
What is w
And what is the power output
Is it the same as work and W is just a fancy way of saying joules or what
Please help

Credendovidis
Jan 8, 2009, 05:51 PM
Please state the full wording of the question in your paper.
What you posted here is rather unclear, and unsuitable as basis for homework help.

:)

Capuchin
Jan 9, 2009, 12:11 AM
a W (Watt) is 1 J/s (Joule per Second). It's a unit of power.

You can easily calculate the power from the energy that is needed to raise the weight (PE = mgh) and the time taken (power = energy/time)

ebaines
Jan 9, 2009, 12:34 PM
Power can be calculated as work (or energy) per unit time as Capuchin says, but it is often easier to use force times velocity. You are given the person's weight (in Newtons) - this is the force he must overcome to climb the rope. His velocity in m/s can be calculated from the time it takes to climb the rope. Multiply the two together, and you get a result that has units Nt-m/s; this is equivalent to Joules/sec, or watts.