Statics: Lesson 43 - Centroids by Calculus Example Problem

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Пікірлер: 49

  • @mattrodriguez2750
    @mattrodriguez27503 жыл бұрын

    You really scared me there when you just stared at you work in silence

  • @EntisarMehdi

    @EntisarMehdi

    6 ай бұрын

    😊😊

  • @georgesadler7830
    @georgesadler78302 жыл бұрын

    Professor Hanson, thank you for another classic Statics lecture on Centroids using old fashion Calculus. A solid background in advanced mathematics would be helpful to any student in Statics.

  • @emt4921
    @emt49213 жыл бұрын

    Guys, if you took Calculus 3, you can assume your mass density function to be 1 (constant), and do the double integrals for mass and moment about the region. I got x=4.5 and y=3.6 that way. Hope it works.

  • @tylerstanton494

    @tylerstanton494

    3 жыл бұрын

    Yes. Absolutely do this

  • @alinaveed1793

    @alinaveed1793

    2 жыл бұрын

    could you link a video or something explaining this further? thanks

  • @joshuamendez425

    @joshuamendez425

    2 жыл бұрын

    @@alinaveed1793 kzread.info/dash/bejne/iYKOmtiGl8S2l8o.html

  • @quadriibrahim2106

    @quadriibrahim2106

    Жыл бұрын

    Yes, there's a formula

  • @Bekdigitalchannel377
    @Bekdigitalchannel3772 жыл бұрын

    PHILIPPIANS 4:13 THANK YOU FOR YOUR WORD OF GOD YOU SHARE US AND TOUGHT US MECHANICS MY GOD BLESS YOU YOU AND YOUR ALL FAMILY.FROM ETHIOPIA COUNTRY

  • @RK-tr7wo
    @RK-tr7wo4 жыл бұрын

    Great example Mr. Hanson!!

  • @firstlegend5105
    @firstlegend51052 жыл бұрын

    If anybody has a problem finding y bar. This is explained by Prof. Jeff in the Statics: Lesson 44 at the timestamp 20:35. In that problem, you don't flip the strip but instead use your (height of the shape x (height of the irregular shape - half of the height of the irregular shape)). That will find you ydA. The value you should get is 72.9. While dA stays the same at 20.25. So y bar is 3.6

  • @adi2.054

    @adi2.054

    Жыл бұрын

    By height of the irregular shape do you meant of the rectangle with base dx? Or the actual shape?

  • @dakpotor1

    @dakpotor1

    Жыл бұрын

    Can you explain further? I tried and I wasn't getting the answer

  • @firstlegend5105

    @firstlegend5105

    Жыл бұрын

    @@adi2.054 I meant by the equation of y=-1/6x²+2x which is the curved equation of the line

  • @firstlegend5105

    @firstlegend5105

    Жыл бұрын

    @@dakpotor1 In order to find integral of ydA, you can simply keep the equation of dA as it is, don't change it. But the tricky part is how do you find the "y". To find out y, you would have to locate the centre of the height of the strip. The height of the strip you already found it in the dA equation, ignoring the dx. You need to half that value of the height of the strip. Next, you need is the line of the strip which corresponds on it. This is obtained from the equation of the of the curved line. Next, to obtain the ydA, it is given by: (height of the strip) *(line equation of the curve - (1/2 height of the strip)). The limits are 0 to 9

  • @bbcoolk9178

    @bbcoolk9178

    11 ай бұрын

    What a legend!@@firstlegend5105

  • @omarhegab
    @omarhegab7 ай бұрын

    I can't express my gratitude to you sir.

  • @kelseyhranicky3475
    @kelseyhranicky34752 жыл бұрын

    thank you for helping me get an A in statics

  • @stdmitri9711
    @stdmitri97114 жыл бұрын

    Please can you do the y bar as well, with those given equation?

  • @mangomasher7254

    @mangomasher7254

    6 ай бұрын

    3.6

  • @klausdunayev7078
    @klausdunayev70782 жыл бұрын

    It seems that to find Y bar you have to find the length of dA, which would be x2 minus x1, but I cannot find a way to express the x1 of the parabola as a function of y to do that. What am I missing?

  • @kensonmalupande2424
    @kensonmalupande2424 Жыл бұрын

    Excellently explained, keep it up sir

  • @ld4677
    @ld46778 ай бұрын

    Time 8:35 “so that becomes” was that moment for me when I was like “thank god because 9^3 does not equal 81…” lol thank you as always got entertainment and education!!!

  • @mhk417
    @mhk4173 ай бұрын

    عمي انت وردة شرحك يخبل

  • @Jasonvoobhggg
    @Jasonvoobhggg Жыл бұрын

    This is absolute calculus!

  • @rickcereceda3889
    @rickcereceda38892 ай бұрын

    Hi Professor, I am confused because dx is not really over the X axis, instead should the dA rectangle be perpendicular to the line y=0.5x ?

  • @huriamazige1141
    @huriamazige1141 Жыл бұрын

    Good thinking

  • @ambrose_8
    @ambrose_83 жыл бұрын

    When solving for y-bar, what would be your limits? from 0 to what? As far as i can tell, instead of 0 - 9, you would need the height, which isn't given?

  • @jasonmalouin9580

    @jasonmalouin9580

    3 жыл бұрын

    Your upper bound would be the maximum height of the upper function. To find the maximum for the upper function, find the derivative of it, set y-prime = 0 , and solve x. Then take that x-value, and plug it back into the original y equation. This will give you the maximum value (Hint: the height is 6). You'll integrate from 0 to 6 with respect to y. Get both of those 2 functions in terms of y, (so, x=) and then do (right function - left function) under the integrand. Solve.

  • @ambrose_8

    @ambrose_8

    3 жыл бұрын

    @@jasonmalouin9580 Thank you!

  • @JulieanGalak

    @JulieanGalak

    3 жыл бұрын

    Note also you'll have to do the integration in two pieces. First piece is from y=0 to y=4.5, where the "top" of the dA strip is the parabola and the "bottom" of the strip is the straight line. Second piece is from 4.5 to 6, where both ends of the dA strip are the parabola. That last part is fairly tricky.

  • @dejaunerambally6557

    @dejaunerambally6557

    3 жыл бұрын

    how to find upper function equation of x in terms of y? (x=..)

  • @puizhistephenteu1885

    @puizhistephenteu1885

    3 жыл бұрын

    @@jasonmalouin9580 how to find the upper equation of x?

  • @jaysuto
    @jaysuto3 жыл бұрын

    please how do i get the equation of dA for Y bar?

  • @user-yx6is2et5s

    @user-yx6is2et5s

    4 ай бұрын

    did you figure it out?

  • @puizhistephenteu1885
    @puizhistephenteu18853 жыл бұрын

    why dun show for y-bar... it is hard

  • @akiil_ii
    @akiil_ii5 ай бұрын

    you are the best

  • @DoesNotChemPute
    @DoesNotChemPute Жыл бұрын

    I think there was a mistake at point 7:15 in the video where it should be 9^3 = 729 and not 9^2 = 81 UPDATE: nevermind, I see this is corrected at point 9:10 in the video after its erased. Thank you for all your videos btw!

  • @tomsawyergaming9250
    @tomsawyergaming9250 Жыл бұрын

    does the ybar here is 4.725?

  • @mangomasher7254

    @mangomasher7254

    6 ай бұрын

    no

  • @nihalulubay8200
    @nihalulubay8200Ай бұрын

    I was trying to solve the problem and I made a mistake, I look the question and I said this integral can not be negative, i looked again and solved the problem. Then i watched the video to see how did you do, and you made the same mistake that I did

  • @Bugatti0wner
    @Bugatti0wner3 жыл бұрын

    The mistake me made was that he took x^3 of 9 as 81.

  • @amandadusabe9225

    @amandadusabe9225

    3 жыл бұрын

    I thought I was the only one that noticed

  • @jonathanbanda5395
    @jonathanbanda5395 Жыл бұрын

    xcellent

  • @mehps20
    @mehps203 жыл бұрын

    The moment he knew he messed up.

  • @braybray7837
    @braybray783711 ай бұрын

    mmmmmmmm static