Why is the volume of a sphere V=4/3*pi*r^3? (calculus disk method)

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  • Опубліковано 28 вер 2024

КОМЕНТАРІ • 46

  • @bprpcalculusbasics
    @bprpcalculusbasics  4 місяці тому +2

    Check out the volume of a cone proof 👉 ua-cam.com/video/drpxZ1aztWE/v-deo.html

    • @falcon3548
      @falcon3548 4 місяці тому

      can you do more calculus proofs please? I am a geometry student and this is very interesting.

  • @AncientBulldozer
    @AncientBulldozer 4 місяці тому +8

    I literally watched your previous video yesterday and in the morning I used the volume method you taught to derive the sphere volume and by sheer coincidence youve uploaded this video today 😂

  • @flowingafterglow629
    @flowingafterglow629 4 місяці тому +4

    These types of "rotate around the axis" volume calculations were probably my favorite part of Calculus II
    I remember when were learning geometry volumes in 4th grade and we got to the volume of the cone = (1/3)*pi*r^2*h and I asked, how do we know that it is 1/3 of a cylinder? The teacher gave a good answer of, maybe you fill it with sand and see that it takes three of them to fill the cylinder, which is empirically ok, but I was very happy when I got to Calc II and could derive it analytically. I finally got my question answered exactly.

  • @brendanward2991
    @brendanward2991 4 місяці тому +3

    That was so satisfying.

  • @SokomoKudiomi-h6l
    @SokomoKudiomi-h6l 2 місяці тому

    I feel like I'm looking at a beautiful artwork without understand total of his beauty. But I want someday understand

  • @akuntumbal1485
    @akuntumbal1485 4 місяці тому +3

    This is beautifull

  • @RadhakrishnanNair-zn8vh
    @RadhakrishnanNair-zn8vh 3 місяці тому

    Great interpretation...Sir...Thank You very much...

  • @justinterrill2131
    @justinterrill2131 4 місяці тому +1

    Calculus now makes sense.

  • @niom9446
    @niom9446 4 місяці тому +56

    Now do it without calculus

  • @mehmetalivat
    @mehmetalivat 4 місяці тому

    next time could you make video for solve sphere volume with jacobian matrix ?

  • @JakkAuburn
    @JakkAuburn 4 місяці тому

    Is it possible to derive the formula for the surface area of a sphere in the same way? Just instead of calculating the area of the entire slice of a semi-circle, we calculate the length of the hypotenuse of triangles which we then make progressively more narrow so they end up giving us the arclength of the semi-circle?

  • @megumn6214
    @megumn6214 4 місяці тому

    in em field theory class we do this in spherical coordinates and I think it's easier to understand and visualize but you need to know vector algebra 🤓

  • @Upward3D
    @Upward3D 4 місяці тому

    Nice.

  • @gallentespeterjohn6543
    @gallentespeterjohn6543 4 місяці тому

    Cool!

  • @jamescollier3
    @jamescollier3 4 місяці тому +1

    +C 😅

  • @Getsomewaterplease
    @Getsomewaterplease 4 місяці тому +1

    Why the surface area of the ball is 4*pi*r^2

    • @davidhowe6905
      @davidhowe6905 4 місяці тому +1

      dV/dr = 4pi r^2; so 4pi r^2 dr gives you the volume of a hollow sphere of area 4pi r^2 and thickness dr.

  • @LuigiElettrico
    @LuigiElettrico 4 місяці тому

    This should be taught in the elementary school :P

  • @duckyoutube6318
    @duckyoutube6318 4 місяці тому

    I think everyone understands the pi*r^3 part.
    Its the 4/3 part that is very strange.

  • @FreshBG
    @FreshBG 4 місяці тому

    👋

  • @Sg190th
    @Sg190th 4 місяці тому +3

    Now we need the same with a circle and circumference.

  • @Nobodyman181
    @Nobodyman181 4 місяці тому +2

    Pleeeeasseeee find Volume of 4th dimension sphere and 4d volume of 4d sphere 😢🙏🙏🙏

    • @happend
      @happend 4 місяці тому

      I believe that volume is not the unit you mean, but the answer is the Integral from 0 to r of 2 * (4/3) * π * (√(r^2 - x^2))^3 dx.

    • @Nobodyman181
      @Nobodyman181 4 місяці тому +1

      @@happend thenk you

    • @happend
      @happend 4 місяці тому

      @@Nobodyman181 I hope I've helped ^^

  • @stefanmi1
    @stefanmi1 4 місяці тому +2

    You're starting with the assumption that the formula for volume of a disk is known. Why not assume nothing and use polar coords? That's the way we learned it. And when you convert the Pythagorean formula to polar you get triple int of rho^2 * sin(phi) d(rho) d(theta) d(phi) with rho from 0 to r, theta from 0 to 2*pi, and phi from 0 to pi.

    • @hishamhamed5033
      @hishamhamed5033 4 місяці тому

      That's the approach I'd take.

    • @rodrigocunha7828
      @rodrigocunha7828 2 місяці тому

      Share the link, please

    • @Engy_Wuck
      @Engy_Wuck Місяць тому

      ha just did this video: "Volume of a sphere with a triple integral"

  • @hibosmo
    @hibosmo 4 місяці тому +1

    bro, why this pop up in my notifications? im getting PTSD from university calculus D:

  • @professorsogol5824
    @professorsogol5824 3 місяці тому

    What is the curvature?? Is it measured in degrees or radians? Is it the radius of the circle that has its center on a line perpendicular to the tangent of the curve at the specified point?

  • @BleuSquid
    @BleuSquid 4 місяці тому

    I love the Tau vs Pi argument because it's fun to think about... but it was the comparison of the derivation of the volume of a sphere, to other well known equations that come to us through integration, that made me a believer in Tau.

  • @sinekavi
    @sinekavi 4 місяці тому

    Were you able to solve the integral @bprp calculus basics?

  • @МаксимАндреев-щ7б
    @МаксимАндреев-щ7б 4 місяці тому +3

    The sphere coordinates are here:
    x = t cos(u) cos(v)
    y = t cos(u) sin(v)
    z = t sin(u)
    -pi/2

  • @Ninja20704
    @Ninja20704 4 місяці тому

    Can this be done without calculus though, I wonder.
    When I asked my calculus teacher they said that this wasn’t the first/original way they came up with the formula, so I have been wondering how you could prove it without calculus.

    • @hrayz
      @hrayz 4 місяці тому

      Calculus, of this nature, is a short hand for a Limit Sum as ∆x->0

  • @HarisRehmanGG
    @HarisRehmanGG 4 місяці тому +2

    Now do surface area