Today in physics class we were discussing the conservation of energy using a ball on a spring as the example. When the instructor completed the problem one of the students stated that the value of K (spring constant) that we found was different (by a factor of 2) than the value of K calculated using Hooke's Law. The instructor could not figure out why the values of K were not the same. Why are they different?(adsbygoogle = window.adsbygoogle || []).push({});

Potential Energy(before)=Potential Energy (after)

(1/2)kx^2+mgh = (1/2)kx^2+mgh

ball on spring at rest = ball on spring extended

2mgh

---------- = k is not equal to k= F/delta h

X^2

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# Homework Help: K in Hookes Law vs. Spring Potential Energy

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