Mechanics of Materials: Lesson 25 - Angle of Twist Due to Torque, Torsion

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[@yaadav2102]

At Uni idk how our professors get hired. They are absolute amateur and they take weeks to explain whatever we learn from Mr.Hanson 15mins'videos. Thank You Mr.Hanson.

[@justinking9266]

at 17:37 you use 2 pi over 180 to convert when it should be pi on 180. i love your videos, they are incredible! so easy to understand

[@Shnarg100]

It was just a simple mistake.

[@philipjovelolesco3754]

@@Shnarg100 no, its a simple mistake.. look, all of his calculations were messed up due to that mistake... hahaha, im a learner too but i just couldnt agree with you..

[@suleymantnr6749]

@@philipjovelolesco3754 at least teacher would give this solution 8/10 grade.

[@chandlerrushford8464]

I was about to say !! I'm not tripping pi = 180 degrees

[@spideytown2542]

yeah, true bro

[@judemancilla6726]

I have a solids exam tomorrow morning, so today I've binge watched a hefty sum of your videos. I'm very grateful for these, especially during this difficult time where help is extremely limited. Thank you, Prof. Hanson!

[@Dimitrios_Sanchez]

How was it? I have solid exams next week and these videos are very helpful for me too

[@CluckYou21]

@@Dimitrios_Sanchez 100% on mine. Watch his videos, do fundamental problems, and homework problems. Make a good note sheet. Easy!

[@mohamedasmarie6351]

At this moment I have the same of your feeling when u wrote your comment 10 months ago So I hope you passed it ❤️

[@craftyporky5584]

Same situation 3 years later lol, hope to do well!

[@kristibester8642]

As an engineering student in South Africa during a global pandemic, I have had to do a lot of self-learning. These videos have helped me greatly to prepare for my final strength of materials exam. Thank you!

[@brunogallego7507]

Im from SA> How is it going? still doing eng?

[@Ben-mi9mm]

Professor, these videos are invaluable and I GREATLY appreciate your teaching methods. It's a crying shame that most Professors aren't this good or show that they care as you do. Infinite thanks to you sir.

[@DaftDriver]

For the last step, should the conversion be 2pi/360 = 1 radian? With that I got the angle of twist of 30.76 degrees

[@graysonnipper1814]

Yea even doctors make mistakes, should be 33.28 degrees from 0.581 rads

[@zadockmaloba1047]

360 deg = 2π rad ... Thus 1 rad = 360/2π

[@upsrank5995]

yeah ,that was the only mistake

[@zeebaka]

I learned more about this topic in 15 minutes here than in multiple weeks of my structures class, amazing.

[@faditemeiza2675]

the angle in degrees is wrong cause it should be 16.66*2= 33.33 degrees I guess the mistake is 2Phi/180 should be only Phi/180 or 1rad =57.3 degrees and 0.581 *57.3= 33.33 degrees

[@alishad9777]

Angel of twist, ha ha. i really enjoy your lighthearted humor

[@t.e.d.d1385]

Thank you very much professor, I had problems about the CCW and CW determination, I didn't know that I should apply it first Also thank you for explaining the topic in solids courses in an easy and fun way.

[@ismailibrahim7626]

I have the same problem, did you figure it yet? If so can you tell me.

[@delemadison9085]

The reaction was ccw but the torque’s cw

[@mishaanikanov5340]

Why do profs who earn 80CAD/hour can't explain the same way?

[@jujuu1339]

Isn't the polar moment of inertia wrong? I thought C is supposed to be the point of interest (ie. in terms of radius)

[@rabahalishah5124]

you are literallly king

[@rayinoz]

Thanks for this vidéo. U make it easy for us to understand torsion.

[@maetheresebatusin8866]

Thank you for this. But will you not minus the angle of twist of CD because its direction is opposite? i hope you can enlighten mi sir!

[@tbenvo24]

For each section the internal torque is clockwise (written in black between the gears). This makes the angles of twist for each section all clockwise. So he sums the angles of twist to get the total clockwise angle of twist.

[@ixXCloud]

@@tbenvo24 Understood, I had the same query

[@efealtun2247]

how do you decide cw or ccw torsion Mr Hanson? It doesnt work if you want to decide according to internal forces diagram!

[@elliewolcott6254]

Thank you so much!! I was really struggling with this in class.

[@manuboker1]

Wonderful solids lessons!! really taking the time to explain the problems along with a good sense of humor :))

[@Ahmed-Afkir]

Hi Mr Henson, Maybe it is a mistake but 2pi=360 degree. So 0.581 rad should be 33.28... degree.

[@danielopoku5587]

Thank youuu!

[@spanishguitarworld5583]

love you sir saving me

[@Josh-rd5dw]

hello professor, if for example you cut a beam and it says clockwise, does that mean you put the negative sign in the equation (-t in this case)?

[@delemadison9085]

The reaction was ccw but the torque’s cw

[@charityabenacudjoe8542]

Please what happens when the torque between a member is anticlockwise.do we have to negate it's angle of twist ?

[@parthpatel4125]

I think you would just subtract it instead of adding it when you take the sim for the angle of twist

[@alejandronava6110]

I am studding for my Master admission test, thank you!

[@patrickwu7026]

I love you

[@sumikokwok2122]

Are the signs +/- arbitrary for the torsional shear stress and angle of twist? So we just write what we get mathematically or do we write the absolute value and specify the direction at the end?

[@delemadison9085]

There’s no such thing as minus it just indicates the direction 🤷🏻‍♂️

[@shadanaladin4796]

thanks so muchh

[@guillermoflores2685]

Shouldn't the tensions be negative since they are moving clockwise?

[@verlgrant1437]

You could have just kept it as KN's since it cancels out with the GPa

[@TheMadridTv]

N to Pa, kN to Kpa, mN to Mpa, gN to GPa.

[@sofiamaeillut5531]

Where did he get the 75 GPa?

[@MattyMakes]

this was the value for modulus of elasticity from the textbook

[@lethabomphahlele9095]

please advise where does the 20 to the fourth and 125 to the fourth come from now?

[@pizzaguy58]

Comes from Dee’s Law

[@scott337]

It's from the inner and outer diameter except you need it as radius so the values are halved

[@yigitcan824]

It's comes from formula for polar moment of inertia

[@orlandojr.martelino4922]

wala lagi lesson 19 sir????

[@shawnbadanjek9561]

It is not that a short shaft is harder to twist, it will just twist less. The longer the shaft the bigger the angle of twist will be.

[@wbzial]

That's why L is in the numerator of the equation of phi.