(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 180-g wood block is firmly attached to a light horizontal spring, Fig. 6-26. The block can slide along a table where the coefficient of friction is 0.30. A force of 20 N compresses the string 18 cm. If the spring is released from this position, how far beyond its equilibrium will it stretch on its first string?

2. Relevant equations

F=kx

Elastic PE = 1/2*kx^2

F_fr=μ_k*F_N

3. The attempt at a solution

We have 20 = 0.18k where k is in N/m. So k= 1000/9. Then this means the elastic potential energy is 1/2*20*(0.18)^2=1.8 J. Work due to friction is F_fr*displacement=0.3*0.18*9.8*displacement=.5292*displacement=1.8, and solving yields ≈3.4 m. Not correct, apparently.

Can anyone show me where I went wrong?

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# Homework Help: Displacement of wood block originally attached to spring

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