cents/ tension

[Robert Scott]

John Fortiner asked:

> Anyone out there have a formula that will calculate tension change
> if you input the cents change of a given wire??
> Example - if a wire is under initially under 150lbs. tension and undergoes
> a change of 7 cents (up or down) what is the tension change on that wire?

The exact answer involves exponentials, but for small changes like 7 cents, this approximation will do:

Tension factor = the square of (1 + .00057879 x cents)

In your example of +7 cents, this would be 1.00495153 squared = 1.008119.

So the 150 lbs. would go up to 151.22 lbs.

For larger cents changes, this approximation is less accurate.  For example, this approximation for 100 cents would say that the tension would go up to 167.77 lbs, while the true answer is 168.37 lbs.

Robert Scott
Ypsilanti, Michigan