- #1
NewProgramma
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Hi everyone,
The problem below kinda confuses me...i've spend half an hour staring at this problem lol.
Homework Statement :
Q: A bent wrench is used to apply a moment of 221 Nm to the hexagonal nut. If the applied force F is 507 N and the angle θ is 21°, find the distance d. Answer in metres.
http://imgur.com/pLjSJkQ
http://[noparse]http://imgur.com/pLjSJkQ[/noparse]
https://courses.kpu.ca/pluginfile.php/287327/question/questiontext/205374/1/856670/q1.jpg The attempt at a solution:
Here is what I tried to do:
Assuming: clockwise moment = negative.
First:
break F into components: 507cos21 = Fx and 507sin21 = Fy.
Second:
Since Fy is along the line of 'd' it has zero moment at the "bent pivot" (not at the nut).
But Fy will exert a moment at the hexagonal nut: so break Fy into components: 507sin21sin28.
Third:
find net moment: -(507cos21)*d + (507sin21sin28)*0.3 = -221
So, d = 0.52m
But the correct answer given to us is: 0.26m
I think I might have mad an error with the moment at "the bent pivot". Since "-(507cos21)*d" equals to the moment at the "bent" and not at the Origin(hex nut)...should I shift the moment at the bent to the origin(nut)?
Or I can think of it as part of the net moment?
I'm still a bit confused about the Net moment at the Origin(nut), does the Net moment mean the sum of all the moments acted on the body, regardless of where it acts? Or does all the moments have to be on the Origin?
Thank you all for the generous help.
The problem below kinda confuses me...i've spend half an hour staring at this problem lol.
Homework Statement :
Q: A bent wrench is used to apply a moment of 221 Nm to the hexagonal nut. If the applied force F is 507 N and the angle θ is 21°, find the distance d. Answer in metres.
http://imgur.com/pLjSJkQ
http://[noparse]http://imgur.com/pLjSJkQ[/noparse]
https://courses.kpu.ca/pluginfile.php/287327/question/questiontext/205374/1/856670/q1.jpg The attempt at a solution:
Here is what I tried to do:
Assuming: clockwise moment = negative.
First:
break F into components: 507cos21 = Fx and 507sin21 = Fy.
Second:
Since Fy is along the line of 'd' it has zero moment at the "bent pivot" (not at the nut).
But Fy will exert a moment at the hexagonal nut: so break Fy into components: 507sin21sin28.
Third:
find net moment: -(507cos21)*d + (507sin21sin28)*0.3 = -221
So, d = 0.52m
But the correct answer given to us is: 0.26m
I think I might have mad an error with the moment at "the bent pivot". Since "-(507cos21)*d" equals to the moment at the "bent" and not at the Origin(hex nut)...should I shift the moment at the bent to the origin(nut)?
Or I can think of it as part of the net moment?
I'm still a bit confused about the Net moment at the Origin(nut), does the Net moment mean the sum of all the moments acted on the body, regardless of where it acts? Or does all the moments have to be on the Origin?
Thank you all for the generous help.
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