Energy in a Spring-Mass System - Help

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In a horizontal spring-mass system with a spring stiffness of 235 N/m and a mass of 0.3 kg, the initial compression is 7 cm and the initial speed is 3 m/s. The user attempts to apply the Energy Principle to determine the maximum stretch, using the equation Kf + Uf = Ki + Ui + W. They calculate the final potential energy but arrive at an implausible maximum stretch of 7 m, prompting doubts about their calculations. A suggestion is made to ensure proper unit conversion, particularly converting the initial compression from centimeters to meters. The discussion highlights the importance of accurate unit conversion and energy balance in solving spring-mass system problems.
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Energy in a Spring-Mass System - Help! :)

1.A horizontal spring-mass system has low friction, spring stiffness 235 N/m, and mass 0.3 kg. The system is released with an initial compression of the spring of 7 cm and an initial speed of the mass of 3 m/s.



(a). What is the maximum stretch during the motion?


The Attempt at a Solution



So I tried using the Energy Principle to find the maximum stretch;

Kf + Uf = Ki + Ui + W

Kf = 0
W= 0 (I think right because there's no outside force?)

SO: 0 + (.5)(ks)(s^2)final = (.5)mv^2 + (.5)(ks)(s^2)initial

By plugging in variables I got that;
(.5)(ks)(s^2)final = 5758.85 J

(s)final = SQRT(2(5758.85)/(235N)) = 7m

(s)final = 7m

This isn't the right answer, which also sort of makes sense because the stretch shouldn't be the same as the compression. Which makes me think that my initial equation is flip flopped or something of the sorts.
 
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Your energy looks too large. Did you convert the 7cm to meters?
 


Going to try that now.
 
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