Calculating velocity of a block on a slope using work theorem

AI Thread Summary
The discussion focuses on calculating the velocity of a block on a slope using the work-energy theorem, specifically the equation Wnet = change in KE. The user initially set up the problem with the wrong angle between the work and force, leading to an incorrect velocity calculation of 0.900 m/s. Upon reevaluation, they corrected the angle and found the correct answer to be 0.6 m/s. This highlights the importance of accurately determining angles in physics problems. The user successfully identified and corrected their mistake after stepping away from the problem.
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Homework Statement



http://www.screencast.com/users/ntrinh3/folders/Jing/media/7b6a2810-2827-44c3-adfc-cd27d564b812

Homework Equations



Wnet=change in KE

The Attempt at a Solution


so I made the coordinate with x positive in right direction and y is positive up.
Fdcos30-mgh=.5mv^2
40*.2*cos30 - 5*9.8*sin15*.2 = .5*5*v^2
I got velocity to be .900

The correct answer was .6
 
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oh nvm. I stepped away from this problem and realized the angle between the work and force was wrong.
 

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