Calculating Work and Speed on a Ramp

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The discussion focuses on calculating the work done by various forces acting on a suitcase being pulled up a ramp. Key forces include the applied force, gravity, friction, and the normal force, with the total work contributing to the suitcase's kinetic energy change. Participants emphasize the importance of correctly identifying and summing these forces to determine the work done, rather than relying solely on calculus. Additionally, the work-energy theorem is highlighted as crucial for finding the suitcase's speed after traveling a specified distance. Accurate calculations hinge on careful attention to force direction and the correct application of formulas.
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Homework Statement


A luggage handler pulls a suitcase of mass 16.3 kg up a ramp inclined at an angle 22.0^\circ above the horizontal by a force F of magnitude 147 N that acts parallel to the ramp. The coefficient of kinetic friction between the ramp and the incline is 0.264. The suitcase travels a distance 4.15 m along the ramp.

Find work done by force F, gravity, friction, the normal force, and the total work done on the suitcase.

Also, if the speed of the suitcase is zero at the bottom of the ramp, what is its speed after it has traveled 4.15 m along the ramp?

Homework Equations


The Attempt at a Solution


https://lh3.googleusercontent.com/_z0seeexOzus/TXscN0-sBsI/AAAAAAAAALs/IzFXWo-6lAE/s800/IMG_20110312_000306.jpg
 
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Well, since the work is the integral of the force, once i get the force i just use the fnint() function on my ti-83 to find the work...so i didn't write it out. so if i can find the correct force, the work is easy to find. but something is wrong with my forces. but thanks for being a jackass. i really appreciate your condescending attitude towards people who are just asking for help on a forum designed to help people with these sorts of things...

and just in case you need this too, here's the page where i tried to find velocity. and i even wrote out a generic integral on here so you know what i did..

IMG_20110312_151608.jpg
 
When you took the sum of forces in the x direction, you assumed that the acceleration was 0. This is not necessarily the case. You can use Newton 2 in that direction to solve for the acceleration. However, this question is not asking for the acceleration.
Once you identify all the forces, which you have done, and the magnitude and direction of these forces, you can find the work done by each. You don't need the calculus to do so when forces are constant...but you need to watch plus and minus signs and use the dot product rule for work done by a force.

Then, the work energy theorem states that the sum of the work done by ALL forces is the kinetic energy change. You must add them all up first before calculating the speed.
 
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