Tufe

Picha ya tufe

Rediasi au nusukipenyo (= r) cha tufe

Tufe ni umbo la gimba linalofanana na mpira au chungwa. Lakini wala mpira wala chungwa ni tufe kamili.

Katika elimu ya hisabati, hasa jiometri tufe ni jumla la nukta zote zilizopo na umbali uleule (=rediasi, nusukipenyo) kutoka nukta nukta moja (kitovu cha tufe).

Tufe ni mzunguko wa duara katika wanda (dimension) la tatu.

• Kitovu cha tufe ni nukta iliyopo katikati yake yenye umbali sawa na kila nukta kwenye uso wake.
• Nusukipenyo cha tufe ni umbali kati ya kitovu chake hadi nukta yoyote kwenye uso wake
• Uso wa tufe ni eneo linalojumlisha nukta zote zenye umbali wa nusukipenyo kutoka kitovu

Mjao

Mjao wa tufe (=V) unaelezwa kwa fomula ifuatayo:

$\!V={\frac {4}{3}}\pi r^{3}$

$\pi$ (tamka pi) ni namba ya duara inayolingana takriban na 3.1416.

Eneo la uso wa tufe

Eneo la uso wa tufe (=A) hukadiriwa kufuatana na fomula ifuatayo:

$\!A=4\pi r^{2}$

Viungo vya Nje

• Spheres (math is fun)
• Sphere (scienceforkids) Archived 26 Aprili 2015 at the Wayback Machine.
• Sphere facts (kidsmathgame)
• Sphere: Definition, Formulas & Quiz
• What is a Sphere? How Are Spheres Made?
• Sphere (PlanetMath.org website)
• Mathematica/Uniform Spherical Distribution
• Outside In. 2007-11-14. Archived from the original on 2007-09-01. https://web.archive.org/web/20070901111142/http://video.google.com/videoplay?docid=-6626464599825291409. Retrieved 2007-11-24. (computer animation showing how the inside of a sphere can turn outside.)
• Program in C++ to draw a sphere using parametric equation
• Surface area of sphere proof.