Interesting question of Stress Concentration | GATE 1992 - Mechanical

[@karthikeyanr616]

In brittle materials stress concentration at tip of the crack is??

[@BabaFakruddin-]

U cleared it in a lucid way sir..

[@vasusrivastava8638]

In made easy solutions they have given answer as 190 MPa without even discussing anything about Stress Concentration Factor

[@lonewolfgaming5245]

Thank you sir.

[@learnwithb2138]

Thank you sir 💙💙💙

[@saikatkarmakar6633]

The problem is interesting because when the plate is large, d/w

[@schandra5395]

Thank you very much sir

[@educationhub6241]

Chapter wise videos kaha milenge,, full lecture

[@ExergicGATE]

You can visit EXERGIC website for all course details. For any further queries, you can call on 9536651816 or mail at [e-mail] Thank you.

[@hajarathvali]

Hi sir..Kt can be ignored for ductile material under static load..

[@rakeshpanda8113]

In case of 5 cm , what will be the answer??

[@premnathv3083]

dear sir, you are making those topics interesting as well as knowledgeable. this really makes me buy ur exergic videos. thank you for this question , it was really helpful. i

[@mannymarjeet8614]

Simply amazing! Thanks a lot.🙏💕

[@lokendraduttjoshi9823]

Sir in ductile material stress concentration factor not much affect .can we consider as nominal stress as answer(190)

[@ManiKandan-zj2lr]

What happens if we did not consider stress concentration factor?

[@kalyankanna00]

We will get wrong answer bro

[@vineetuniyal9615]

Thanx sir I just have debate this by others for options b and c And I m also getting c But you have fully opened the concept. Thanx again

[@abhishekdarnal]

Questions like these are the sole reason why most aspirants lose faith in gate exam.

[@arjunoralakkote1522]

Thank you so much for delivering classes in English .... excellent quality contents.

[@AshishSingh-hx4fr]

Sir, we can find the exact answer by theory of elasticity formula for circle discontinuity , we prefer for lecture stress concentration nptl

[@saikatkarmakar6633]

I think that if the answer, 285 is exactly correct then the logic provided here is incorrect. Because in that case, large plate doesn't mean that d/w 0+) so that, nominal stress tenses to 95Mpa from its positive side (nominal stress --> 95Mpa +) and Kt tenses to 3 from its negetive side(Kt --> 0-) so that the maximum stress tenses to 285 Mpa from some side. I'm saying this because as per the graph it seems that the answer is 285MPa whenever d/w=0.1 . So, it is also not exactly 2.85 when d/w

[@vineetuniyal9615]

I am wondering that how many geniuses has actually solved that question at that time

[@KakarotM99]

Back then gate was held with data book

[@Jaihari8081]

Sir , in nptel machine design pdf while explaining stress concentration they have done bit different. According to them , the ratio of max stress and nominal stress is termed as theoretical stress concentration factor but while using relation ,sigma max = sigma (1 +(2b/a)) , the mentioned sigma is stress that the body is subjected to without considering the hole condition ( no net cross section area condition ).Same way things have been explained in Shigley's mechanical engineering design book. Please guide as this way hole size wouldn't matter for calculating maximum stress generated due to hole .

[@ExergicGATE]

Please refer more lessons and solved examples in both the sources you mentioned. It will be clear to you.

[@sahibdantya9891]

Actually I have a doubt regarding nominal stress. Nominal Stress is the stress calculated on the basis of the net cross section of a specimen without taking into account the effect of geometric discontinuities such as holes, grooves, fillets, etc.But here we have taken into account the hole diameter.So can you please explain it.

[@nehag542]

He is so cute 😬

[@Apollo-dq6jm]

Tharak apni jagah, parai apni

[@deepaksadigale3016]

Perfect explanation,,,

[@arindambaruah2450]

At the point of 0 shear force ...we get maximum bending moment or bm can be either maximum or minimum

[@happyfinance1806]

Very interesting way to explain plz further bring this type of question

[@rakeshpanda8113]

In the book of made easy , they give the answer 190mpa...

[@studyfun7875]

Wow the explanation is so good and nice

[@mehulghoghari4050]

IN NPTEL LECTURE BY PROFESSOR RAJESH PRASAD THEY CONSIDERED SIGMANOT AS EXTERNAL APPLIED STRESS

[@ExergicGATE]

Please refer to NPTEL PDFs as well where it is clearly mentioned which section to take. When hole area is less, they may take any section due to small difference. But correct way is explained in the video.

[@AnishManikandanneo]

This one was very interesting. Thank you for uploading it..:D

[@Calibrating_Consciousness]

kt=2.85

[@movi12]

Is it me or did he just multiplied stress with area to get stress again?! 🤔 The answer is 285, nominal stress is 95 and multiplied 3 is max stress. But second look he equated forces, but nominal stress flowing will still be 95 through out, there is no question of adding stress concentration if there is no change in the flow. Still confused 😕 please watch Jeff Hansons video on stress concentration on why I'm confused. Please explain stress concentration with this video, I know there is one done already, but with this to be clear please

[@IpsitDhal]

mind blown...*ucking genius...thanks for sharing free stuffs ... please share more please 😍😍😍

[@utkarshsinghalus3085]

Sir sigmanot ki vale aapne 95 Kyu nahi li aap sigmanot ki value nikal rhe hai

[@ExergicGATE]

Sigma(not) is different than applied sigma. That is what I have told that all other institutes are doing mistake at. Please refer to any credible source to learn concepts :)

[@bagishkumar264]

Bhaiya nominal stress is known as maximum stress

[@aspirant9303]

Amazing

[@akashkumar-ld2bw]

Thank u sir for this, I have also done mistake of multipling 3. Please upload some other confusing questions like this.

[@yashgaur6115]

Gr8

[@mvssushma7042]

Helpful

[@chandansharma2694]

Wow

[@bleedingred-white-blue8749]

This question I believe was put there to make mistakes.

[@ganeshkrishnan5048]

@EXERGIC SIR WHAT IS Kt?? Can you help me with that

[@ashish31416]

Thank you. This is very interesting. One can find more on www.fracturemechanics.org/hole.html Using empirical relation, \sigma_{max} happens to be nearly 285.1995 MPa

[@girishpatel2192]

Thank u so much sir..... Thanks for concluding it, i believe 285 is the right answer.... But in karnataka pgcet mechanical 2017 paper the answer is 100 Mpa.....

[@kingvkronaldo.9273]

Thank u sir. U r Making mechanical engineering more interesting. Respect sir

[@bleedingred-white-blue8749]

I don't know I should be happy or sad after seeing this question.

[@kalyankanna00]

🤣🤣🤣

[@Nitesh_Bihar]

,,👍👍

[@deepankumar482]

i am the first viewer😀

[@Mohankumardash]

sir I am afraid but your solution is wrong To obtain the maximum stress in a circular hole we need to multiply with applied stress only i.e. 95Mpa in this case I am saying so by taking reference from the book of Applied Elasticity by Martin.H.Shaad There in polar form of airy's stress function you can see this example page no 177 of 2nd edition

[@ExergicGATE]

As far as GATE is concerned, in case of any contradiction or confusion always go with NPTEL. The solution done by us can be verified from NPTEL.

[@adityay1970]

Sir then In this case ,The correct ans is indeterminate as the answer is not matching

[@Gasturbine]

Last viewer🤸🤸

[@vijayvinoba2039]

From graph for d/w=.05 K=2.85 so Smax=285 MPa Or Kt=3-(3.13d/w)+3.66(d/w)^2-1.53(d/w)^3 Kt=2.8524 Then Smax=285 MPa Or Kt=1+2(a/b)=>3. Since a=b (circular initially before load) t not given so for unit thickness Kt varies from .95 to 1 i.e Kt= 2.85 to 3 Then Smax=285 MPa Smax/Snom=Kt Snom= P/wt=P/(w-d)t