Solving Spring, Block, Incline & Friction: Help Needed (Pictures Included)

AI Thread Summary
The discussion centers around a physics homework problem involving a block-spring system, where students are confused about the correct interpretation of the spring's compression. The key equations provided relate to energy conservation, specifically the transformation of elastic potential energy into gravitational potential energy. A critical point raised is the ambiguity in the problem statement regarding whether the spring is compressed to or from a specific length, which affects the solution. It is suggested that using conservation of energy principles is the most effective approach to solve the problem. Overall, clarity on the spring's equilibrium length is essential for determining the distance the block travels.
jjmont17
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So we took a quiz in class, no one got it right so now its take home and I am lost.

Homework Statement


2rqnlgj.jpg

24lpmya.jpg



Homework Equations


.5kxi -Fkd= .5MVf^2
h=dsin(tht)
umgh=fk
fk=ukN



The Attempt at a Solution


I really do not know where to start i tried
(1/2)(500n/m)(12.0)-(3.25)(500n/m)(d)=.5(2)(vf^2)
 
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Unless the question was meant to say "the block-spring system is initially compressed by 12.0 cm" rather than "the block-spring system is initially compressed to 12.0 cm", this problem is unsolvable. Without knowing the spring's equilibrium length, it's impossible to find how high it travels; if the equilibrium length is 12.1 cm, that's obviously going to give a different result than if it's 54 cm.

If we assume the spring's compressed 12 cm from equilibrium, conservation of energy is the best way to solve this problem. The spring has no kinetic energy at the bottom and none at the top, but it turned elastic potential energy into gravitational potential energy and heat. Express this as an equation, then solve for the distance travelled.
 
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