• Support PF! Buy your school textbooks, materials and every day products Here!

Tension on a String

  • Thread starter epena
  • Start date
  • #1
1
0
I'm trying to figure out the sag of a wire hanging between two objects. If I string a wire between two structures and tension the wire 5000 lbs in the horizontal direction, I can estimate the shape of the wire to be parabolic and use the equation: Sag = (W*L^2)/(8*T), where W=Weight of wire, L=Span between two supports, and T=Horizontal Tension to calculate the sag. If now I add a much heavier wire to the first wire, how can I arrive at the new Sag and Tension for the two wire combination? I am assuming the same temperature for both installations (60 degrees F). The first wire is .65 lbs/ft; the second wire is 7.8 lbs/ft. I am trying to solve the problem without neglecting the initial wire's weight.
 

Attachments

Last edited:

Answers and Replies

  • #2
5,428
291
Have a look at this

http://mathworld.wolfram.com/Catenary.html

If two different wires hang in the same curve they must be joined along their length, so you can pretend it's one wire with the average density (?)
 

Related Threads on Tension on a String

  • Last Post
Replies
11
Views
7K
  • Last Post
Replies
7
Views
1K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
4
Views
1K
  • Last Post
Replies
8
Views
6K
  • Last Post
Replies
5
Views
2K
Replies
1
Views
447
Replies
9
Views
5K
Replies
1
Views
15K
Replies
20
Views
52K
Top