# Series of springs

1. Feb 22, 2006

### ownsail

If two springs, having different spring constants, are in a series (lined up, NOT parrallel): is the Force pulling the spring = (sum of spring constants)*(distance stretched) ?

2. Feb 22, 2006

### phucnv87

No, no. If the force apply to the $$1^{st}$$ spring, the equation will be

$$F=k_1\Delta l_1$$

3. Feb 22, 2006

### ownsail

so the same force is applied to both springs?

4. Feb 22, 2006

### ownsail

in other words, if F = kx:
F=(k1)(x1)
and
F=(k2)(x2)

but not F=(k1+k2)(x1+x2)

5. Feb 22, 2006

### phucnv87

That's right, and the equivalent constant is

$$\frac{1}{k}=\frac{1}{k_1}+\frac{1}{k_2}+...+\frac{1}{k_n}$$