Line tension problem help

[drkidd22]

I need help trying to figure this problem out.

 

[tiny-tim]

Hi drkidd22!

Show us what you've tried, and where you're stuck, and then we'll know how to help!

 

[drkidd22]

So I have this so far trying to find Tbd.
It will be the same for Tbe as they are the same distance away from A.

 

[drkidd22]

distance on horizontal=√(18^2+18^2)=18*√2 ft
distance on vertical=21 ft
∴θ=angle in between pole & cable=tan-1(18*√2/21)=50.479 degree
Σall horizontal force=0
1680=2T sinθ
∴T=1088.944 lb
Σall vertical force =0
R=2T cosθ [R= reaction force at A ]
∴R=1385.924 lb

Not sure if it's correct

 

[pongo38]

How many components are there to the reaction at A (at most)? You ask if it is correct. But you could determine this yourself by recognising that there are at most 6 equilibrium equations for the whole thing...

 

[drkidd22]

There are three forces at A
Fx
Fz
Fy

 

[pongo38]

So have you calculated any of them so far?

(By the way your physicsp148.doc document has just one line and it is sloppy, or incorrect or inconsistent. If T is a force, why do the units have ft at the end?)

 

[pongo38]

when you say "1680=2T sinθ ", exactly what free body diagram are you considering the equilibrium of?