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Question
Tension
Tension  
Sir,
I have a certain doubt with a numerical asking to find out the tension in two strings. The question is as follows:
"A horizontal rod AB is suspended at its ends by two strings as given in the figure(image attached). The rod is 0.6m long and it's weight is 0.3kgf acting at G where AG is 40cm. Find the tension in the strings X and Y."

I don't want any calculations but a simple explanation about how to solve it would help.

Answer
As with all such problems, you pick a rotation point to make one of the torque terms zero, then write down a solvable torque equation.  From there, you can write down any number of statics equations to solve for the other one.  In statics, the choice of a rotation point is the beginning of approaching the problem almost all the time.  If you can't solve it after that (especially in this case, I'd choose point A), you're pretty much out of luck.

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Dr. Stephen O. Nelson

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I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.

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I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

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Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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