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 2 years ago
Determine the moment of each of the three forces about point B. Please see attached figure.
 2 years ago
Determine the moment of each of the three forces about point B. Please see attached figure.

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redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0I know how to find it about point A, but I am having difficulty seeing how to find it for point B.

Yahoo!
 2 years ago
Best ResponseYou've already chosen the best response.0Seperately Solve the hinge forces...:)

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0I don't understand what you mean.

azolotor
 2 years ago
Best ResponseYou've already chosen the best response.0He means, solve for the force at each of the points where there is an angle and then sum them to see where the net force is

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1You guys have missed the question. What is being asked is what the moment due to each force. Can you help the questioner?

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1I'll do it then. What is the definition of the moment of a force?

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0The moment of a force is its ability to create rotation.

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1Yes, but mathematically and precisely, with a formula?

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0M = F*d, where d is the distance between the point of application and the pivot

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0(btw thanks for your help, I have been lost for hours)

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1Yes. Now, let's start with F3. What's the moment due to that force?

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1..the moment of F3 about B? Well, what's the distance of the application of the force from B? Zero. Can F3 make something rotate *around* B? No. Therefore the moment due to F3 is zero.

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0ah!! that's what I thought! but I thought it would be wrong bcs it was 0

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0bcs the position vector at B is <0,0,0> and crossing it with the F3 vector would give zero.

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0But one question, would not the perpendicular component of F3 try to produce some moiton that vertical bar?

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1The question at a qualitative level is this: can a force applied at a point cause other things to rotate about that point? And the answer is no. It might make that point and the solid attached to it move, but it doesn't cause rotation around that point per se. Hence: A force applied to a point causes no rotation about that point.

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0its the same as if I go to the center of the bolt and try to make it rotate applying a force right on the center of rotations. no rotation would happen!

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0I have to move at least an infinitesimally small amount away from that center of rotation for it to actually rotate (no matter how large the force). Motion may occur in the form of displacement, but no actual rotation about that point :D

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0for f2. I think it goes like this:

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0the position vector would be : <3, 4 , 0>

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1No, you want the positive vector RELATIVE TO B

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1Which will be just r = <0,4,0>

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0hmmm would not that be moving to the right of B and up from B?

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0oh yes! sorry I was doing F1 mistakenly !

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1oh right. yes, F2. Doing them backwards because F1 is the most complicated.

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0r = <0, 4 0 > ; F2 = < 300*sin(60) , 300 *cos(60) , 0 >

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1check your sin and cos there

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0ah, i see that I did. I was putting it on the wrong side

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0< 300*cos(60) , 300 *sin(60) , 0 >

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1Yes. Ok, you've got it. I'll leave you with F1 now by yourself.

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0I have dyslexia and its hard to see things sometimes! Thanks for your patience

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0for F1, r = < 3 , 4 , 0 >

redpanda
 2 years ago
Best ResponseYou've already chosen the best response.0F1 = < 250*sin(30) , 250*cos(3), 0 >

JamesJ
 2 years ago
Best ResponseYou've already chosen the best response.1Looks right (30 obviously). Now calculate the cross products
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