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PhysicsOPhun

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**Springs, Kinetic Friction, and Distance...help me please**

**1. In the figure below a 1.4 {\rm kg} block is held at rest against a spring with a force constant k = 740 {\rm N/m}. Initially, the spring is compressed a distance d. When the block is released, it slides across a surface that is frictionless except for a rough patch of width 5.0 {\rm cm} that has a coefficient of kinetic friction mu = 0.44.**

**2. Questions: Find d such that the block's speed after crossing the rough patch is 2.3 {\rm m/s}. /b]**

[PLAIN][PLAIN]http://img84.imageshack.us/img84/1249/111it7.jpg

I apologize if I messed up the template, this is my first post so I will hope to not make any mistakes again if i did this time.

Also, my work as of right now for this problem consists of 2 pages front to back with writing all over, I really wouldn't know where to start and am so confused at this point that I could really use a push.

[PLAIN][PLAIN]http://img84.imageshack.us/img84/1249/111it7.jpg

**3. Relevant equations: Ok, I know how to apply the kinetic friction to the mass but how do I start this equation? What effect does the force of the spring have on the velocity and how does the defined distance work out? I really want to understand this but am afraid that conceptually it's hard for me to work out. Any pointers or all applicable equations would greatly be appreciated so I could get on with this. I have been doing Chemistry since 6am and my brain is just not tickin right now...**I apologize if I messed up the template, this is my first post so I will hope to not make any mistakes again if i did this time.

Also, my work as of right now for this problem consists of 2 pages front to back with writing all over, I really wouldn't know where to start and am so confused at this point that I could really use a push.

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