Calculating Spring Weight: Formulas and Tips for Compression Testing

[bucky1andonly]

is there any formulas for a spring, or any way at all to calculate the weight needed to compress a spring, or do you just have to experiment

 

[quasar987]

Mmh the law is "you have to exert a constant force of kx to maintain the spring stretched a distance x from its position of equilibrium", where k is the spring constant. But ultimately, you have to find k experimentally.

 

[WhyIsItSo]

quasar987 is correct; k can only be determined experimetally. Once you have that:

A simple form of Hooke's law
$$F=-kx$$
F = force. k = spring constant. x = displacement from relaxed (not stretched or compressed). Note the right side is negative to denote "equal but opposite".

Also:
$$PE = \frac{1}{2}kx^2$$.

 

[Doc Al]

The negative sign in Hooke's law indicates that the direction of the restoring force is opposite to the displacement from the unstretched position. For example: Displace the end of the spring to the right, the spring force acts to the left.

 

[russ_watters]

...if you don't have K, though, you can still calculate it from the properties of the material and shape of the spring.

 

[bucky1andonly]

thx, that helped a lot

 

[Hootenanny]

...if you don't have K, though, you can still calculate it from the properties of the material and shape of the spring.

For more information;
http://scienceworld.wolfram.com/physics/AtomicSpringConstant.html