- #1
Taiden
- 9
- 0
Hey everyone. First time poster here.
I was helping a friend do some Statics homework (I completed the course last Fall), and I ran into a really unsettling problem.
I have done this problem over several times with the same result.
When I do the problem only summing forces in the X and then Y direction, I get an answer that "checks out."
When I do the same problem, but FIRST solve for tension using sum of moments about point R, I get a result for tension that does NOT check out.
I have tried doing this with simple algebra methods, and using cross products to determine the magnitude of tension. EVERY TIME I USE MOMENTS I get the same answer.
Here's the problem:
http://img829.imageshack.us/img829/3564/stuffcw.png
I just sketched this up. R is just a reaction force. In the actual problem it's a rocker end that is butted up against a floor and a wall. Tension is a wire that is connected to the same wall.
When I sum forces in X and then Y, I get
T = 167.2 N
R = 192.9 NWhen I sum moments I get
T = 83.56 N
then sum moments in Y direction gives me R = 96.42
Just looking for anyone to try to figure it out with moments and see if they can get it to work.
Thanks,
Luke
I was helping a friend do some Statics homework (I completed the course last Fall), and I ran into a really unsettling problem.
I have done this problem over several times with the same result.
When I do the problem only summing forces in the X and then Y direction, I get an answer that "checks out."
When I do the same problem, but FIRST solve for tension using sum of moments about point R, I get a result for tension that does NOT check out.
I have tried doing this with simple algebra methods, and using cross products to determine the magnitude of tension. EVERY TIME I USE MOMENTS I get the same answer.
Here's the problem:
http://img829.imageshack.us/img829/3564/stuffcw.png
I just sketched this up. R is just a reaction force. In the actual problem it's a rocker end that is butted up against a floor and a wall. Tension is a wire that is connected to the same wall.
When I sum forces in X and then Y, I get
T = 167.2 N
R = 192.9 NWhen I sum moments I get
T = 83.56 N
then sum moments in Y direction gives me R = 96.42
Just looking for anyone to try to figure it out with moments and see if they can get it to work.
Thanks,
Luke
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