pretty clear explanations. i came for the zero force members but i ended up watching almost the whole video. I actually had fun learning this as well. thanks a tons
Many many thanks for this lecture professor. I love your tone in class and you make engineering seem like high school work all over again. l like how you take your time to explain even the details cause that is what matters. I am doing civil engineering at the University of Debrecen and you would do the engineering world justice if you came and taught the teachers how to do this. once again thank you and much appreciation
I started out as an architecture major in college in 1976, as an elective I took the first structures/statics class in civil engineering where we learned the exact topic he is presenting....this one course changed my mind and I switched to mechancal engineering, graduated and went to work for the largest oil company in the world and retired three years ago from the same company....I am happy that I can have not forgotten a lot of this and I am following along with this lecture very easily and basically picking up where I left off in college....great lecture/presentation
@@boriskoz8042 It was a combination of things...I was working for an architectural firm drafting and helping with designs, started in high school and was working part time while in college. The architectural professors were all theoretical and artsy and I was using practical real world in my design classes and they did not like that...a good friend was in engineering and he and were studying one night in the library and I was seeing the work he was doing and I got interested and that is when I decided on engineering. Now, I started my mechanical engineering career in the oil industry and retired with the same company I started with, ExxonMobil, and I will tell you right now, engineering is an outstanding career, pays extremely well and there are many different paths you can take. I retired as an engineering advisor and my area of expertise was in high speed rotating machinery, hot gas expanders in cat cracker (gasoline) units....you will not go wrong, it is not easy and you study your butt off but it is worth it. If you have any more questions, please let me know.
Thank you Professor! I have been terrified trying to solve trusses. Your method and explanation on how to setup and solve trusses is the best. Thank you again!
Hi Dogan, yes I think finding and eliminating zero force members is pretty fun and definitely useful. Writers of engineering exams tend to include zero force members in their problems pretty frequently too. I wish you luck on your exam, whenever it actually happens!
Solve for Tag: Ratio of similar triangles. Slope (4/5) = 606.25/Tab ==>> Tab = 757.8 lb :: Tag = Sqrt( square(606.25)+(square757.8)) = 970.46 lb. Force Tab may be solved first. Although this works when ( x force ) required first. I prefer the elegance of method given by instructor. I took statics and dynamics MANY years ago at University, and the courses were very difficult for me to thoroughly comprehend. Rarely, does an instructor of this quality happen .
Finally thank you 💛💛💛 I couldn't understand how to find zero force member until I watched this video my final exam is the next week you helped me alot thank you again💛💛💛💛
I followed along and understood the first about 40 minutes of your video, then you threw in a formula or equation that I wasn't familiar with where you calculated Rdy to be 593.75 lbs. which makes sense since slightly more of the 1200 lbs total force will be on joint A. What prerequisite lecture/info do I need to watch so I can learn this? It's a little over my head. This is a really good video. Thanks you so much for sharing!
I'm glad you found it helpful! I have several other playlists you might also be interested in as well: ENGR122: th-cam.com/play/PL1IHA35xY5H52IKu6TVfFW-BDqAt_aZyg.html (Introduction to Statics and Engineering Economics) ENGR220: th-cam.com/play/PL1IHA35xY5H5sjfjibqn_XFFxk3-pFiaX.html (Statics and Mechanics of Materials) MEMT203: th-cam.com/play/PL1IHA35xY5H6G64khh8fcNkjVJDGMqrHo.html (Dynamics) Thanks for watching, and I hope it went well!
For Joint AG, I have never seen this formula for x and y section previously. What formula do you use; Tension AG times 4/(4^2+5^2)^1/2 for x and y axis? I never seen this before.
You are right to have the intuition that long tension members won't benefit from the addition of zero force members for stabilization the way that compressive members do. Thanks for watching!
When finding BE, I tried it by summing up the forces in the x direction and I got 2111.01, I see you got 170.12 for BE when you used the sum of forces in the Y direction. I thought we were supposed to get the same answer using either the sum of forces in the x or y direction. Could I please get an explanation? 1:16:54
Even though I am not a structural engineer I really do enjoy watching your lectures. One thing I am interested in, which probably many others have written about as well, is the software/hardware you are using in your lectures. I really like the paper look of the screen and the hand written style.
I'm glad you enjoy them! I use microsoft onenote 2007 (last version with customizable toolbars) on a Fujitsu T901 (gen 2 i7 w/ 16G ram and a Wacom digitizer). I use camtasia to do screencapture and editing. Thanks for watching!
James R. Miller,my grand father wrote and had published a book,1930's on how to build rafters and trusses,my dad has a copy of the book,my grand dad was tired of no unity in angles.
@@TheBomPE I saw a copy of a paper back book,J.R. Miller wrote,he is from Arab,Alabama,the book is on building rafters and pitches of roofs,he was born between 1922 and 1925,hope this helps,,,please let me know,thank you.
To hold a 2d structure in equilibrium generally requires 3 components of reaction. The most typical way to do this is with one pin (2 components) and one roller (one component). With just 2 rollers, the structure would still have a mobility number greater than 0, meaning in theory, it would be unstable. In practice you might get away with situations that look as though they are equivalent to 2 rollers if friction forces present are sufficient to react any intentional or unintentional unbalanced applied force components in the direction of the structure's mobility.
@@TheBomPE Studying for my PE. your video is so helpful and I love your humor!!! A lot of other videos on TH-cam go really fast. Your videos are so clear and you explain everything.
Multiplying by trig functions is only one way to get x or y force components. Since I had slope information given in the problem and not an angle, I used that information directly. The first video in this series shows how that can be done and why. th-cam.com/video/I5RYv2JDKus/w-d-xo.html
I sat through method of joints in a solid mechanics class at NC State in 1982! Definition of terms and the describing of zero force members makes this a great review of this technique/analysis.
I think its Pythagorean, since he is finding the length of the hypotenuse he instead used the Pythagorean since we don't know its value yet. 4 / square root of 4^2 + 5^2, tan = adjacent / hypotenuse
I learned this in '84 in technical high school and in Spanish. I'm surprised I can still fully understand this, even in English. Being able to write the equation in the calculator helps a lot. Thank you very much professor, I've truly enjoined the whole exercise !!! Your explanation is fantastic.
i wish my professor can be more like you, i am hardly learning anything from him. thankyou so much for uploading this
Happy to help!
pretty clear explanations. i came for the zero force members but i ended up watching almost the whole video. I actually had fun learning this as well. thanks a tons
I'm very glad it was helpful! Thanks for watching!
Many many thanks for this lecture professor. I love your tone in class and you make engineering seem like high school work all over again. l like how you take your time to explain even the details cause that is what matters. I am doing civil engineering at the University of Debrecen and you would do the engineering world justice if you came and taught the teachers how to do this. once again thank you and much appreciation
come teach at Purdue Fort Wayne please
How's the pay? Ha ha ha
I started out as an architecture major in college in 1976, as an elective I took the first structures/statics class in civil engineering where we learned the exact topic he is presenting....this one course changed my mind and I switched to mechancal engineering, graduated and went to work for the largest oil company in the world and retired three years ago from the same company....I am happy that I can have not forgotten a lot of this and I am following along with this lecture very easily and basically picking up where I left off in college....great lecture/presentation
what about it made you change your career path and what was your original goal? - a guy about to go to college in a year
@@boriskoz8042 It was a combination of things...I was working for an architectural firm drafting and helping with designs, started in high school and was working part time while in college. The architectural professors were all theoretical and artsy and I was using practical real world in my design classes and they did not like that...a good friend was in engineering and he and were studying one night in the library and I was seeing the work he was doing and I got interested and that is when I decided on engineering. Now, I started my mechanical engineering career in the oil industry and retired with the same company I started with, ExxonMobil, and I will tell you right now, engineering is an outstanding career, pays extremely well and there are many different paths you can take. I retired as an engineering advisor and my area of expertise was in high speed rotating machinery, hot gas expanders in cat cracker (gasoline) units....you will not go wrong, it is not easy and you study your butt off but it is worth it. If you have any more questions, please let me know.
All students who he taught should cherish the education he transferred to them.. I'm here wishing i had a teacher/lecturer like him
You are very kind! If you get a chance, maybe you can come to Louisiana Tech University and take a class with me someday!
Thank you Professor! I have been terrified trying to solve trusses. Your method and explanation on how to setup and solve trusses is the best. Thank you again!
Glad I could help! Thanks for watching!
Thank you very much professor , what you're doing it amazing
757.8 lb is negative "Compression"
I love the zero force member finding strategy, it was fun indeed:)
Hi Dogan, yes I think finding and eliminating zero force members is pretty fun and definitely useful. Writers of engineering exams tend to include zero force members in their problems pretty frequently too. I wish you luck on your exam, whenever it actually happens!
Solve for Tag: Ratio of similar triangles. Slope (4/5) = 606.25/Tab ==>> Tab = 757.8 lb :: Tag = Sqrt( square(606.25)+(square757.8)) = 970.46 lb. Force Tab may be solved first. Although this works when ( x force ) required first. I prefer the elegance of method given by instructor. I took statics and dynamics MANY years ago at University, and the courses were very difficult for me to thoroughly comprehend. Rarely, does an instructor of this quality happen .
Woww. Professor. I try to learn your teaching skills. I appreciate it.
Thanks! All the best to you!
Finally thank you 💛💛💛
I couldn't understand how to find zero force member until I watched this video my final exam is the next week you helped me alot thank you again💛💛💛💛
I'm glad it was helpful! I hope you did well on your exam!
I followed along and understood the first about 40 minutes of your video, then you threw in a formula or equation that I wasn't familiar with where you calculated Rdy to be 593.75 lbs. which makes sense since slightly more of the 1200 lbs total force will be on joint A. What prerequisite lecture/info do I need to watch so I can learn this? It's a little over my head. This is a really good video. Thanks you so much for sharing!
At 1.75x speed this is a perfect video
FDE is incorrect because correct answer is 1061.4
No, you are incorrect. The value of 1070.4 lb is correct for the tension in member DE. You may want to go back and check your work.
Thank you, my Engineering Applications performance final is tomorrow!!!
Follow up: Performance final went really well, I found it very easy. Thank you so much!!!
I'm glad you found it helpful! I have several other playlists you might also be interested in as well:
ENGR122: th-cam.com/play/PL1IHA35xY5H52IKu6TVfFW-BDqAt_aZyg.html
(Introduction to Statics and Engineering Economics)
ENGR220: th-cam.com/play/PL1IHA35xY5H5sjfjibqn_XFFxk3-pFiaX.html
(Statics and Mechanics of Materials)
MEMT203: th-cam.com/play/PL1IHA35xY5H6G64khh8fcNkjVJDGMqrHo.html
(Dynamics)
Thanks for watching, and I hope it went well!
Helped a lot for my exams this week! Should have found this sooner!!!
I'm glad it helped! Thanks for watching!
Wish I found this video when I was learning trusses in college, life would have been little easy, brilliant teaching skills sir.
Thank you! All the best to you!
55:14 Is the sum of forces Fy =606.25*4/(square root(4+5))- TG 606.25*4/(square root(4+5)) =0 correct ??
"OKAY?"
Ha ha, yeah, I say that a lot :)
At work just practicing, always had a challenge with trusses, until I watch this video thanks.
I'm glad I could help! Thanks for watching!
Thanks for this teaching sir...
I am indeed grateful..
Please sir how can I know where to draw the slope I mean the Right angled triangle
it was quite meritorious listening to you thanks Professoor
Glad you found it rewarding! Thanks for watching!
For Joint AG, I have never seen this formula for x and y section previously. What formula do you use; Tension AG times 4/(4^2+5^2)^1/2 for x and y axis? I never seen this before.
check out th-cam.com/video/I5RYv2JDKus/w-d-xo.html
Thank you so much:)))!!!
No problem 😊
Thank you very much sir. I was really confused with this part. Not anymore. Helped a lot.
Would we need any zero force member at CE for stability if the members BC and CD were in tension? Or is it unnecessary?
You are right to have the intuition that long tension members won't benefit from the addition of zero force members for stabilization the way that compressive members do. Thanks for watching!
When finding BE, I tried it by summing up the forces in the x direction and I got 2111.01, I see you got 170.12 for BE when you used the sum of forces in the Y direction. I thought we were supposed to get the same answer using either the sum of forces in the x or y direction. Could I please get an explanation? 1:16:54
Solving -(-757.8)+(-890.625)+TBE*5/sqrt(5^2+4^2)=0 for TBE results in 170.1. You must have had an error somewhere in your process.
@@TheBomPE I sure did! I missed the extra negative sign. Thank you sir!
Good instruction.
I'm glad you liked the video! Thanks for watching!
Hi, I have checked the FBD by Fy summ and the result was not zero. It was 1200 lb. That's not good.
606.25 + 593.75 - 500 - 700 = 0
@@TheBomPE
i have summurized the forces in the members: Ray+Rdy+Tag*(4/sqr(4^2+5^2))+Tbg-500+Tbe*(4/sqr(4^2+5^2))-700+Tde*(4/sqr(4^2+6^2))=1200lb
Even though I am not a structural engineer I really do enjoy watching your lectures. One thing I am interested in, which probably many others have written about as well, is the software/hardware you are using in your lectures. I really like the paper look of the screen and the hand written style.
I'm glad you enjoy them! I use microsoft onenote 2007 (last version with customizable toolbars) on a Fujitsu T901 (gen 2 i7 w/ 16G ram and a Wacom digitizer). I use camtasia to do screencapture and editing. Thanks for watching!
James R. Miller,my grand father wrote and had published a book,1930's on how to build rafters and trusses,my dad has a copy of the book,my grand dad was tired of no unity in angles.
Google doesn't give me any results that seem to reference your grandfather.
@@TheBomPE I saw a copy of a paper back book,J.R. Miller wrote,he is from Arab,Alabama,the book is on building rafters and pitches of roofs,he was born between 1922 and 1925,hope this helps,,,please let me know,thank you.
You explain so well. Thankyou.
Hii sr what will happen if we support a truss over two roller
To hold a 2d structure in equilibrium generally requires 3 components of reaction. The most typical way to do this is with one pin (2 components) and one roller (one component). With just 2 rollers, the structure would still have a mobility number greater than 0, meaning in theory, it would be unstable. In practice you might get away with situations that look as though they are equivalent to 2 rollers if friction forces present are sufficient to react any intentional or unintentional unbalanced applied force components in the direction of the structure's mobility.
Great video and good humor!
Glad you enjoyed it!
@@TheBomPE Studying for my PE. your video is so helpful and I love your humor!!! A lot of other videos on TH-cam go really fast. Your videos are so clear and you explain everything.
@@svongsa You are very kind. It feels good to feel like I'm helping!
But on the 54:29 from where did u come from the theta
Multiplying by trig functions is only one way to get x or y force components. Since I had slope information given in the problem and not an angle, I used that information directly. The first video in this series shows how that can be done and why. th-cam.com/video/I5RYv2JDKus/w-d-xo.html
Thank you so much sir ! The zero force rule really help me 🙏
Glad I could help! Thanks for watching!
Can we equate the 4 and 5 to tan twitter
I sat through method of joints in a solid mechanics class at NC State in 1982! Definition of terms and the describing of zero force members makes this a great review of this technique/analysis.
Very good professor.
Can we equate the 4 and 5 to tan twitter
I think you forgot to multiply by Instagram and divide by Facebook.
Hi Sir! How did you get 4 divided (4+5) 53:04 ?
I think its Pythagorean, since he is finding the length of the hypotenuse he instead used the Pythagorean since we don't know its value yet. 4 / square root of 4^2 + 5^2, tan = adjacent / hypotenuse
@@princeiligan5568 I think you mean cos = adjacent / hypotenuse
.....why? :(
Because you signed up to study engineering.
I learned this in '84 in technical high school and in Spanish. I'm surprised I can still fully understand this, even in English. Being able to write the equation in the calculator helps a lot. Thank you very much professor, I've truly enjoined the whole exercise !!! Your explanation is fantastic.