Percentage energy loss (mechanical energy) problem

AI Thread Summary
An object with a mass of 2.0 kg slides down a low-friction incline, reaching a speed of 2.7 m/s at the bottom from a height of 0.50 m. The problem involves calculating the percentage energy loss during this process. The initial approach used the equation mgh(0) + W(other forces) = 0.5mv^2, but the calculations did not yield the correct answer. Suggestions include ensuring the energy loss is calculated by subtracting the initial potential energy from the final kinetic energy and converting the result to a percentage. Detailed calculations are necessary to identify any mistakes in the approach.
poopandpee
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Homework Statement


Problem: An object with mass 2.0 kg slides down a low-friction incline and its speed measured at the bottom is 2.7 m/s. The object starts sliding at a height of 0.50 m over the tabletop and its speed is measured 0.10 m over the tabletop. How big is the percentage energy loss?

Homework Equations

The Attempt at a Solution


My attempt: I've tried using this formula: mgh(0) + W(other forces) = 0.5mv2, where m=2.0 kg, h=0.4 m, and v=2.7 Then I found W(other forces) and divided it by mgh(0). However, that did not give a right answer. Any suggestions?
 
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The sign of the energy loss is a bit questionable but overall the approach is good. Maybe some mistake in the calculations? You didn't show them.
 
Did you remember to multiply by 100 to convert to %?
 
You shouldn't divide by the other work, if your equation above is correct you should subtract mgh(0) to get W alone
 
NateTheGreatt77 said:
You shouldn't divide by the other work, if your equation above is correct you should subtract mgh(0) to get W alone
That appears to be what @poopandpee did before dividing:
poopandpee said:
Then I found W(other forces)
As others have posted, the method sounds correct, but we need to see the details.
 
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