Confusing forces, and friction problem

AI Thread Summary
The problem involves a block of mass m on a 30-degree inclined plane, starting at a height of 2.5 m and sliding down 5 m with a friction coefficient of 0.4. To find the final velocity, the conservation of energy principle is applied, where gravitational potential energy converts into kinetic energy and energy lost to friction. The equations F=ma and Ff=u*Fn are relevant for calculating forces. The absence of a time component suggests focusing solely on energy transformations rather than kinematics. The discussion emphasizes using energy conservation to solve for the final velocity without needing time.
johswill
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Homework Statement


My friend posed this problem to me about a week ago, and I haven't been able to figure it out, it is: So, we've got a block with mass m on an inclined plane of 30 degrees above the horizontal. It is placed at a height of 2.5 m. The coefficient of friction is 0.4. It slides down 5m. What is the final velocity?


Homework Equations


F=ma, Ff=u*Fn


The Attempt at a Solution


I have been able to get everything right, I'm just not sure how to do if it there is not a time component added into the problem, and my friend said you didn't need time.
 
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Try using conservation of energy. All of the gravitational potential energy goes into kinetic energy and energy in overcoming friction.
 

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