I attend K-State for mechanical engineering and this has been the most beneficial video for an explanation for MOI I have seen so far. Fantastic job on presenting the material.
Thanks for posting this. I have been out of school for over 20 years, and now I find myself trying to help one of my nephews with his homework. Guess that is what I get for recommending engineering as a career. LOL!
at table 7:35 i think it's supposed to be 1/12 bh^3 for the inertia, and on the third row, isn't it supposed to be Ix instead of Ic since we've found Ic from 1/12 bh^3?
On 7:55 your equation should be (1/12)(b)(h)^3 otherwise you won't get the numbers shown in the chart, which are .5, 18, and .5. Great video though helped me a lot.
What do you do when you can simplify the cross section as a set of rectangles but not all of them are parallel to an axis? (like a triangle shape profile)
Great vid! While designing the I-beam, to increase moment capacity, the best option is definitely increasing the height without changing any other thing. Increasing web thickness is useful for increasing shear capacity. But is there a capacity type that increasing flange width/thickness is the best option for that?
This video is really helpful. However, how am I going to solve a problem for an I-beam if the height and the width of the web and flanges are not given and just considering the thickness of those two are the same. Though the x'-axis of the cross sectional is given and is equal to 334,000 cm^4. The cross-sectional area is 86 cm^2. It is asking for the moment of inertia at the centroidal axis. I can't solve the problem. Please help.
There's also Myanmar and Liberia, but yes. We have to learn two units instead of one, which just adds another layer of (unnecessary) difficulty to being a civil engineering student.
Can? Maybe. Should have to? Absolutely not. Just about any engineer who actually uses numbers and measurements to perform calculations on a regular basis will agree that English systems of units are stupid. However in my experience, most people who don't (most people period) will argue all day long about how we shouldn't change because they like the fact that they can drive 1 mile per minute at highway speeds, and they're used to feet and inches and don't want to learn something else. Frustrating!
Jorge Rubalcava It sounds like you're looking for the MOI about the Neutral Axis, correct? In that case, it's the same process, except you're finding the moment of the segment's area about said neutral axis. That is to say, either to find the moment of the segment to either the right or left the N.A. because your question asked for the y axis. It would be above or below if it said x axis. This is useful to find the shear flow later on.
Can we calculate the moment of inertia of an L shape by substracting a whole rectangle to the "empty space" as done with the Double T shape in this example?
Yes, but there's not really an advantage as there is for a section that is symmetric from top to bottom. With an L-shape, you have to apply the parallel axis theorem to both the whole rectangle and the empty space, since the centroid of neither of the pieces lies on the neutral axis of the section.
The overall width is 6 inches, and the width of the web is 1 inch. Therefore, the width each of the rectangular areas removed from the rectangle defined by the overall dimensions is one-half of 6 minus 1 or 2.5 inches.
why is moment of inertia to the fourth. like what does MOI even tell us. I'm finding the math easy, but the answer doesn't actually inform me of anything in my head. please help. i struggle with the easy parts
You have to sum up all the y * a, then divide it with sum of the area. From this video, it is the sum of the third column divided by the sum of the first column.
I attend K-State for mechanical engineering and this has been the most beneficial video for an explanation for MOI I have seen so far. Fantastic job on presenting the material.
Thanks for posting this. I have been out of school for over 20 years, and now I find myself trying to help one of my nephews with his homework. Guess that is what I get for recommending engineering as a career. LOL!
My music teacher really don't have this skills to make this lessons more understable. Thank u for saving my music grade.
i just want you to know how much i appreciate you taking the time to explain this. you are an unsung hero
you help a lot !!!!! my exam is coming tomorrow, with your help I think I could get the full point out of that exam!!! thank you !
Great in-depth video, with visuals to understand how to calculate. Thank you sir!
at table 7:35 i think it's supposed to be 1/12 bh^3 for the inertia, and on the third row, isn't it supposed to be Ix instead of Ic since we've found Ic from 1/12 bh^3?
Thanks - I added annotations to that location.
Great work in explaining the concept. It's easy to understand because of your explanation. Thank you.
than for the examples, but how did u git 36.37 for the 2nd rectangular??? i didnt get it
Great video - very clear examples and well organized. Thank you for your hard work and effort.
Agree with previous commentary...best walkthrough of moment of inertia...thank you, Sir!
This video helped me understand how to calculate moment of inertia a lot better now! Thanks a lot!!
everything was clear and now I get how to solve same problem in the video. much thanks
On 7:55 your equation should be (1/12)(b)(h)^3 otherwise you won't get the numbers shown in the chart, which are .5, 18, and .5. Great video though helped me a lot.
How did you get 2.5 on the base when calculating symmetric beam. On the diagram, it was showing 1inch for the height
Thank you for sharing
answered all of my questions without wasting my time! thank you
Thank you so much, reviewing my PE exam and your channel is exactly what i needed for review
Thank you, and good luck with the PE exam!
can you also find the total I and subtract the empty parts if we rotate the I beam and get a H shape?
for the I beam, why is the segments 1 and 3 have similar Ad^2, aren't they both have different distances from the neutral axis?
what is the difference between second moment of area and moment of inertia?
What do you do when you can simplify the cross section as a set of rectangles but not all of them are parallel to an axis? (like a triangle shape profile)
great video but why is it 1/2 instead of 1/12 at 6minutes?
Amazing sir. I always watch your Lectures to prepare my Lectures
at 5:36, was that supposed to be I sub x? not I sub c?
how to get y from d=( 6.5-y) the table from the first method isnt same as the 3rd one u said, please explain
You have explained it so nicely. Thanks for the efforts put in for making this video.
A great, useful, and easy to understand explanation. Thank you for uploading this!
the Ic in the table first method isnt same as Ic at the 3rth one please explain
Sir in second one how is 73.5 came that is value of adsquare
Great vid! While designing the I-beam, to increase moment capacity, the best option is definitely increasing the height without changing any other thing.
Increasing web thickness is useful for increasing shear capacity.
But is there a capacity type that increasing flange width/thickness is the best option for that?
Yes, wider flanges would improve the moment of inertia in the y axis. While thicker flanges improve the beams torsional properties.
how to know which is symmetric axis to find moment of inertia
This video is really helpful.
However, how am I going to solve a problem for an I-beam if the height and the width of the web and flanges are not given and just considering the thickness of those two are the same.
Though the x'-axis of the cross sectional is given and is equal to 334,000 cm^4. The cross-sectional area is 86 cm^2.
It is asking for the moment of inertia at the centroidal axis.
I can't solve the problem. Please help.
Thank you.. I learned in in 10 minutes.. when I couldn't understand it within 6 months..
Thanks! I appreciate your comment.
what is difference of moment inertia and moment ultimate?
Thank you for posting this. It helped me a lot!
Parabéns pela explicação e desenvolvimento. Me ajudou bastante com este jeito mais simples de executar os cálculos.
wow eres catalan?
This video saved my life.
A good engineer can work with any unit.
There is no any units its only american and rest of the world. What a stubborn nation.
There's also Myanmar and Liberia, but yes. We have to learn two units instead of one, which just adds another layer of (unnecessary) difficulty to being a civil engineering student.
Can? Maybe. Should have to? Absolutely not. Just about any engineer who actually uses numbers and measurements to perform calculations on a regular basis will agree that English systems of units are stupid. However in my experience, most people who don't (most people period) will argue all day long about how we shouldn't change because they like the fact that they can drive 1 mile per minute at highway speeds, and they're used to feet and inches and don't want to learn something else. Frustrating!
i really enjoyed when i was enjoying the tutorials
for example, how can we know moment ultimate (moment internal) for IPE 400?
my moment external is 350 kN.m
thanks
example in 7:46 the moment inertia should be 1/12bh^3 not 1/2bh^3
what is d??
whta if the question asked to find MOI about the y axis?
Jorge Rubalcava It sounds like you're looking for the MOI about the Neutral Axis, correct? In that case, it's the same process, except you're finding the moment of the segment's area about said neutral axis. That is to say, either to find the moment of the segment to either the right or left the N.A. because your question asked for the y axis. It would be above or below if it said x axis. This is useful to find the shear flow later on.
thorough and easy to understand. Thanks!!!
265-90
How did you get the 90
hey, so I'm in my first year and my lecturer never taught us how to use and apply the structural steel tables can you please assist?
Najuwah Hamza she never knew.. Haha
So easy to learn and understand. Thank u
Nice, exactly what I needed! Thanks
I've never felt like an engineer I did now, before...
Thank you so much. It is really useful for a student.
Thanks for the explanation with full effort
Ratio 50%, How to calculate the Beam/Built-up/channel/Angle load bearing Strength as per LRFD/EC3/ASD
Thanks! helped me a lot in my studies!
how u get the d in 3rth part of ur video im confused
what is the difference between Ix and I`x
ix = I`x+Ad^2
and how can we get d if he told me find i`x
Can we calculate the moment of inertia of an L shape by substracting a whole rectangle to the "empty space" as done with the Double T shape in this example?
Yes, but there's not really an advantage as there is for a section that is symmetric from top to bottom. With an L-shape, you have to apply the parallel axis theorem to both the whole rectangle and the empty space, since the centroid of neither of the pieces lies on the neutral axis of the section.
For I beam. Why 2.5in for B?
The overall width is 6 inches, and the web thickness is 1 inch. Therefore, the width of material "removed" from each side is 1/2(6-1) = 2.5 inches.
hello sir i have read somewhere that for same area the "stepped i
section" has more strength than that of simple " i section " is it
true...?
no
Thank you! very useful! especially the end increasing case, and extrusion aluminum!
Great video!
Thank you for the great explanation!
Thank you very much, this is very helpfull for my lecture.
thanks for explaining I section(symmetrical). i was looking for it everywhere.
Thanks for such good explanation!
You are a god amongst mortals
how do you get the 2.5? can someone explains to me
The overall width is 6 inches, and the width of the web is 1 inch. Therefore, the width each of the rectangular areas removed from the rectangle defined by the overall dimensions is one-half of 6 minus 1 or 2.5 inches.
8:30 it's supposed to be 1/12 bh^3
you have done a good job , thank you
thanks for the vid! you have a great way of explaining the questions :D
thanks . very good explanation .
Awesome video man! You are better than my professor XD
10minutes video is more useful than 2 hours uni lecture
what about the moment inertia about y axis?
This is the Y-axis, I believe you may be referring to the X axis. We don't calculate the the X-axis because the cross section is symmetrical.
from 7:33 , there you calculated Inertia by dividing bh^3 by 2, not 12!
Mistake from slide
why is moment of inertia to the fourth. like what does MOI even tell us. I'm finding the math easy, but the answer doesn't actually inform me of anything in my head. please help. i struggle with the easy parts
how did u get 4.75 i did'nt get it
4.75 is the y bar wich is (A1*y1+A2*y2)/(A1+A2) he did it go back a little bit maybe you did not pay attention. I hope it helps
Thank you very helpful !!!
Really helpful, thanks!
how did you got the 4.75???? the y(bar)
That's shown from about 2:00 to 3:30.
no it's not
You have to sum up all the y * a, then divide it with sum of the area. From this video, it is the sum of the third column divided by the sum of the first column.
at 3:13, 57/12 = 4.75
6.5?
amazing tutorial, thanks for your time, sir.
Thank you very much, this was clear
Great video! Thank you!
Thank you very much for your explanation!
You just earned yourself a sub, wow!
Thank you so much for the video, I can finally do these problems now!
Thank you so much for this!! This helped me out so much
thank you so much! because of this i was able to answer my activity :)
Can you use metres in your examples, instead of inches
Thank u so much sir ❤️❤️❤️❤️❤️❤️❤️
thank you sir, this video help me a lot.
this is interesting sir
That was very helpful!! (y)
thank you
You sir, are a beauty.
thanks, very helpful
thanks for this one really helps me a lot
You are a hero! :)
should be divided by 12 not 2...
great explain >>thanks♥