I used to use angles, but now I prefer "unit slope" to figure out the vert and horiz components. Interested? The Benefits: 1.) No need to overlay a 2nd coordinate system. (more chances error) 2.) Struggling to find perpendicular moment arm. (more error and creative trig is needed) 3.) Struggling to find angles...phew...I get exhausted following the extra triangles drawn So here it is. Use this Force(IH) is 0.98(run) and 0.19(rise). WTF? Follow, me: horiz comp = 0.98F(IH) and vert comp = 0.19F(IH) Then solve for "magnitude" F(IH). Where did I get 0.98 and 0.19? On slope of top of truss it's run=30ft, rise=6ft. Right? Then calc the hypotenuse(30.594), and divide both run/rise by 30.594. Bingo! But? WTF? is this? This is "unitized" rise and run value based on hyp=1. Thus, multiply by anything force(lbs) or length(ft) and you get the actual component. I know explanation is a little lengthy, but this incredibly minimizes paper scribbling space. Any "old time engineer" will tell it's best way. This is similar to when you have a 3/4/5 triangle configuration. The horiz would be 3/5 and vert comp is 4/5...etc. If you go deeper into trigonometry 0.98 and 0.19 are actually the cosine and sine of the angle. The angle which we don't need to waste time finding, but if you need use arc-cos and arc-sin will confirm the same angle. 11 degrees.
hey that was preety easy... thnks
i was having problem understanding that now its clear to me... all hail civil engg academy😊😊😊
I used to use angles, but now I prefer "unit slope" to figure out the vert and horiz components. Interested?
The Benefits:
1.) No need to overlay a 2nd coordinate system. (more chances error)
2.) Struggling to find perpendicular moment arm. (more error and creative trig is needed)
3.) Struggling to find angles...phew...I get exhausted following the extra triangles drawn
So here it is. Use this Force(IH) is 0.98(run) and 0.19(rise). WTF?
Follow, me:
horiz comp = 0.98F(IH) and vert comp = 0.19F(IH)
Then solve for "magnitude" F(IH).
Where did I get 0.98 and 0.19?
On slope of top of truss it's run=30ft, rise=6ft. Right?
Then calc the hypotenuse(30.594), and divide both run/rise by 30.594.
Bingo! But? WTF? is this? This is "unitized" rise and run value based on hyp=1.
Thus, multiply by anything force(lbs) or length(ft) and you get the actual component.
I know explanation is a little lengthy, but this incredibly minimizes paper scribbling space. Any "old time engineer" will tell it's best way. This is similar to when you have a 3/4/5 triangle configuration. The horiz would be 3/5 and vert comp is 4/5...etc.
If you go deeper into trigonometry 0.98 and 0.19 are actually the cosine and sine of the angle. The angle which we don't need to waste time finding, but if you need use arc-cos and arc-sin will confirm the same angle. 11 degrees.
+trexinvert Thanks for sharing!!
like that unit slope.
Nai DAngeles
Thank you. This was really helpful.
good one
thanks man .your the fucken best
virtual work method fun.
Credit goes to cameraman. .