Why is this wrong, Spring Problem

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The discussion centers on a physics problem involving a block attached to a spring, focusing on calculating the block's speed as it passes through equilibrium. The initial approach incorrectly applies gravitational potential energy instead of elastic potential energy. The correct formula for elastic potential energy is E = 1/2 k Δl², where k is the spring constant and Δl is the displacement from equilibrium. The correct calculation should use this formula to find the speed of the block. Understanding the distinction between gravitational and elastic potential energy is crucial for solving such problems accurately.
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A 2.00 kg block is attached to a spring of force constant 590 N/m as in Figure 7.10. The block is pulled 6.00 cm to the right of equilibrium and released from rest.

(a) Find the speed of the block as it passes through equilibrium if the horizontal surface is frictionless.

We can use potential energy here...MGH=1/2MV^2
2GH=V^2
2(9.8)(.06)=V^2
V=1.0844 m/s

Why is this off?
 
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because it isn't gravitational potential energy... it's elastic potential energy.
 
The elastic potential energy is E=\frac{1}{2}k\Delta l^2[/color]
 
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