Pulleys: Why would my calculated work output be higher than my work input?

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The discussion centers on a physics lab experiment measuring the mechanical advantage and efficiency of pulley systems. The calculated work output exceeds the work input, leading to an unusually high efficiency value. Potential sources of error are being explored, particularly in measurement accuracy. A suggestion is made to consider the mass of any pulleys that moved with the load, which may not have been included in the total load mass. Accurate accounting of all components is crucial for valid results in such experiments.
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Homework Statement


The experiment in my Physics lab today was to determine the mechanical advantage and efficiency of various pulley systems. My calculated work output is higher than my work input, which is causing an abnormally high value for efficiency, and I am attempting to find the source of error. I have attached my data tables and a copy of the lab procedure.

Homework Equations


work output = (weight of load) * (height lifted)
work input = (force measured) * (distance moved)

The Attempt at a Solution


I guess it would be error in measurement, though I am unsure of how this could have happened.
 

Attachments

Physics news on Phys.org
Did you remember to include the mass of any pulleys that moved along with the load in the total load mass? (See step 7 instructions).
 
Thread 'Correct statement about size of wire to produce larger extension'

Thread 'Correct statement about size of wire to produce larger extension'

The answer is (B) but I don't really understand why. Based on formula of Young Modulus: $$x=\frac{FL}{AE}$$ The second wire made of the same material so it means they have same Young Modulus. Larger extension means larger value of ##x## so to get larger value of ##x## we can increase ##F## and ##L## and decrease ##A## I am not sure whether there is change in ##F## for first and second wire so I will just assume ##F## does not change. It leaves (B) and (C) as possible options so why is (C)...
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