Formula for combined spring constant.

AI Thread Summary
To calculate the combined spring constant of two springs connected in series, the correct approach involves recognizing that both springs experience the same tension. The relationship can be expressed as T = k1 * x1 = k2 * x2, where T is the tension, k1 and k2 are the spring constants, and x1 and x2 are the displacements of the respective springs. The total extension is given by T = k_series * (x1 + x2), leading to the formula for the combined spring constant: 1/k_series = 1/k1 + 1/k2. Understanding these relationships clarifies the calculation of the combined spring constant for springs in series. The discussion emphasizes the importance of recognizing tension and displacement in the context of spring mechanics.
nerfed
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Help - Formula for combined spring constant.

Hey, I was wondering if anyone can help me with the formula to calculate the combined spring constant of two springs stuck together (end to end).

This is as far as I've been able to figure it out lol, I can't wrap my head around this formula. The k1 and x1 are the values of the first spring, and k2 and x2 are the values of the second spring respectively.

F(series) = [(k1)*(k2)] * [(x1)+(x2)]
 
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Not sure what that formula means. (The units don't make sense!)

Hint: Realize that two springs in series must have the same tension.
 
Heh, yeah, that's why I need the help.

I need to know how to find the spring constant of two springs connected end to end. That botched equation up there is my attempt at it, so I was wondering if you guys knew it.
 
You should be able to figure it out with the hint I gave. Use your same notation:
T = k_1 x_1 = k_2 x_2

But the tension is also given by:
T = k_{series} (x_1 + x_2)

Play around with these and see what you can do.
 
nerfed,

Here's another hint. If you have a spring with spring constant k and you cut it in two, what are the spring constants (call them k1 and k2) of the two pieces?
 
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