Energy in a Spring-Mass System - Help

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SUMMARY

The discussion focuses on calculating the maximum stretch in a horizontal spring-mass system with a spring stiffness of 235 N/m and a mass of 0.3 kg, initially compressed by 7 cm and moving at 3 m/s. The user applied the Energy Principle, stating that the final kinetic energy plus potential energy equals the initial kinetic energy plus initial potential energy. The calculations initially yielded an incorrect maximum stretch of 7 m, prompting a reevaluation of the energy values and unit conversions, particularly ensuring that the initial compression was converted from centimeters to meters.

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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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