engineering away from circuits (CWM=ACWM)

Thread Starter

lomax1

Joined Feb 6, 2014
27
Hi all,

A uniform horizontal beam: RA to RB is 8m

CWM = (2x20)+(5x5)+(7x30)+(9×15) = ACWM 40 + 25 + 210 +135

Not taking the 1st term (1x15) = (6×20)+(3x5)+(1×30) .I am confused with how you jump to 6x20 (and so on) my logic is to ad the surplus 1 on the end to the first moment of 2 at RA add that to the second moment of 3 to get 6 and x that by 20?
Without being able to draw s diagram its hard to describe. I believe im on the right track...
 

Papabravo

Joined Feb 24, 2006
21,227
I have no clue what track you are on. The diagram isn't just a thing -- it is the ONLY thing. Words fail me here to describe my opinion.
 

MrChips

Joined Oct 2, 2009
30,823
I doubt that anyone here can help you. We have no idea what you are referring to.
Perhaps you fail to provide us with some vital information.
A diagram would also help.
 

Thread Starter

lomax1

Joined Feb 6, 2014
27
Thought it was a long shof as it structural. I couldnt be anymore to the point with my description ( I am sure someone will tell me otherwise)

No worries
 

MrChips

Joined Oct 2, 2009
30,823
What is the meaning or origin of (2x20), for example?

It could mean 2t x 20m, 2mm x 20kg, 2A x 20V, etc.

Where are your units man?
 

shteii01

Joined Feb 19, 2010
4,644
What is the meaning or origin of (2x20), for example?

It could mean 2t x 20m, 2mm x 20kg, 2A x 20V, etc.

Where are your units man?
It looks like we are dealing with Statics problem. EE students are usually required to take one or two "mechanical" courses. I think my school now has a course where they rolled statics and dynamics material into one course. I got lucky in that when I went through the program we had a choice so I took just statics.
 

Thread Starter

lomax1

Joined Feb 6, 2014
27
Yes, equilibriam in beams and pillars etc. (Clockwise movements) CWM have to equal (Anti clockwise movements) ACWM. Do you know anything about this? Im just confused in the huge jump in numbers on the reverse?
 

shteii01

Joined Feb 19, 2010
4,644
Yes, equilibriam in beams and pillars etc. (Clockwise movements) CWM have to equal (Anti clockwise movements) ACWM. Do you know anything about this? Im just confused in the huge jump in numbers on the reverse?
Need much better description of the problem. Which usually done with a picture.

It has been a few years since I took that statics course I mentioned. If I remember basic setup, then the type of the "connections" are important. A beam pinned in place has one set of forces acting on that end. A beam that is not pinned and, for example supported under it, is then allowed to move in one dimension and will have a different set of forces acting on it.

Without a good illustration of the problem setup, I am not even going to bother trying to figure it out. Even if there was a good illustration, I would need to dig up my Statics textbook and my notes to make sure I am doing things right.
 

Thread Starter

lomax1

Joined Feb 6, 2014
27
This is the problem im hitting again and again with this forum (lol) I have no picture just text from a credible ( which I do question) university in the UK. I am armed soley with a text book which does exactly what it says on the tin......'text'. Its very frustrating. No worries thanks anyway
 

Papabravo

Joined Feb 24, 2006
21,227
This is the problem im hitting again and again with this forum (lol) I have no picture just text from a credible ( which I do question) university in the UK. I am armed soley with a text book which does exactly what it says on the tin......'text'. Its very frustrating. No worries thanks anyway
What a steaming pile!!
Draw a picture -- find a scanner. How hard could it be? You're going to have a great deal of trouble in industry if you can't send a picture.
 
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shteii01

Joined Feb 19, 2010
4,644
This is the problem im hitting again and again with this forum (lol) I have no picture just text from a credible ( which I do question) university in the UK. I am armed soley with a text book which does exactly what it says on the tin......'text'. Its very frustrating. No worries thanks anyway
Your presentation of the material is very poor.

If you clearly understand the problem and just having difficulty solving it. Why not draw a picture for us. Label the forces, label the moments. You provided a couple of equations, but we don't know if we are looking at scalar product or at vector cross product.

Frankly I am not interested in playing Game of 101 Questions.



My Statics textbook, from a few years ago.

 

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Thread Starter

lomax1

Joined Feb 6, 2014
27
It looks like we are dealing with Statics problem. EE students are usually required to take one or two "mechanical" courses. I think my school now has a course where they rolled statics and dynamics material into one course. I got lucky in that when I went through the program we had a choice so I took just statics.
What is the meaning of your existence?
 

bertus

Joined Apr 5, 2008
22,278
Hello,

I have moderated (taken from the board) some of your posts.
There is no need to insult the people who are trying to help you.

Bertus
 
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