Derive the kinetic energy of a mass on two springs

AI Thread Summary
The discussion focuses on deriving the kinetic energy equation for a mass attached to two springs. The user attempts to calculate the change in kinetic energy using the integral ΔK = ∫ F(x) · dx, incorporating spring constants and displacement variables. A response highlights the need to specify the limits of integration, suggesting that the calculation should start from a point where kinetic energy is zero. Clarification on the integration limits is essential for accurately determining the kinetic energy at a specific position. The conversation emphasizes the importance of proper setup in physics calculations.
ramialsaiad
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Homework Statement


Hi

I want to derive the equation of kinetic energy for a mass on two springs .. Here is the figure of the system:
http://faculty.ndhu.edu.tw/~clcheng/class-98/gen-phy98/gen-phy98-1-Q2s.pdf

Am I doing right for calculating the kinetic energy for the mass on two springs ?

Homework Equations



ΔK = ∫ F(x) · dx

The Attempt at a Solution



My attempt to solve the kinetic equation is by using this formula :

ΔK = ∫ F(x) · dx

so ΔK = (-2kx^2)/2 + ∫ 2kxL/(√(x^2 + L^2)) = (-2kx^2)/2 + 2kL*√(x^2 + L^2)

Am I doing right for calculating the kinetic energy for the mass on two springs ?

Thanks
 
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Hi Ramialsaiad,

What are the limits for your integral?

You have to integrate between, say, x0 and x. To determine the actual KE at a given point you would need to start at the value for x0 where KE = 0.

AM
 
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