Solving for Kinetic & Potential Energy: Help Needed

AI Thread Summary
The discussion revolves around solving a physics problem involving kinetic and potential energy. The initial equation set up by the user suggests a relationship between kinetic energy and gravitational potential energy. However, there is uncertainty about the correctness of the calculations, particularly regarding the influence of gravity and the normal force on motion. Participants emphasize the need for additional forces or information to accurately solve the problem. The user ultimately reports receiving help in class, indicating progress in understanding the topic.
Robb
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Homework Statement


upload_2016-4-17_19-1-20.png


Homework Equations


upload_2016-4-17_19-1-38.png


The Attempt at a Solution



Kinetic Energy + Potential energy=0

1/2mv^2 = mgcos(20)
100v^2 = 1.96cos(20)
v^2 = .0184
v = .136 m/s

No idea if this is correct or if I should proceed with energy considerations. Please advise.
 
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Under the influence of gravity and the normal force of the incline, the resulting motion is not at constant velocity. Right?

There must be an additional force somewhere to balance the forces.
So, you are missing something.
Is there anything else given in the problem that can be used?
 
Thanks for the response. I got help in class last night!
 

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