Anyone good at maths?

Discussion in 'Waffle' started by mistasfx, Nov 1, 2012.

  1. mistasfx

    mistasfx MISTA SFX

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    Can anyone help me with the following question?

    The force F exerted by a jet of water as it strikes a stationary flat plate at right angles is given by the formula :

    f = pπd2v2 / 4.

    where
    p: 1000kgm3 (density of water),
    d = 0.05m (diameter of the jet),
    π = 3.142 pi,
    F =450 force.

    Determine the velocity v in ms-1 that the jet will deliver the force....

    having a bit of a brain fart at the moment
     
  2. rysk

    rysk Part-time waster

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  3. mistasfx

    mistasfx MISTA SFX

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    i was told last week how to do it but ive forgot and cant find anywhere online to help
     
  4. IV4

    IV4 Currently a newt.

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    The train arrives at 3:30.
     
  5. danwell

    danwell BAAAAAAAAAAAAABE WAIT

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    Mish mash will know
     
  6. justin_credible

    justin_credible Lurker

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    you've just got to re-arrange that motherfucker. Alas its been a while since i did that though im afraid
     
  7. mistasfx

    mistasfx MISTA SFX

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    the workings out ive got are...

    4f = pπd2v2

    4f/pπd2 = v2

    so the square root of v is v2
     
  8. Psychoholic

    Psychoholic Quantum Cunt

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    The derivation for α / α v
    ------------------------
    α / α v * ((d² * v²) / 4) = d² * v / 2
     
  9. fractal

    fractal Well-Known Member

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    dont think he needs to do any derivations...just re-arrange it and make sure the units make sense when u have done so
     
  10. GeeLeb

    GeeLeb Member

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    The answer you are looking for is 3 to the power of batman squared
     
    bn14 likes this.
  11. rob_del_terror

    rob_del_terror - ̿ ̿'̵͇̿̿з=(•̪●)=ε

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  12. Busdriver

    Busdriver Member

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  13. groelle

    groelle Well-Known Member

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    id need a physics book to get that. math isnt the hardest part in there, as fractal said, the units have to fit.
     
  14. mistasfx

    mistasfx MISTA SFX

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    v = 15.138ms

    i got. anyone agree?
     
  15. Harry3

    Harry3 Chuki

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    I disagree, I got 256.891
     
  16. Psychoholic

    Psychoholic Quantum Cunt

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    ^ Verified.
     
  17. mistasfx

    mistasfx MISTA SFX

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    4 x 450 (force) = 1000 x 3.142 x 0.0025 = 7.855

    1800/7.855 = 229.153

    i got 229.153 and the square root of that is 15.138

    show me ur workings
     
    Last edited: Nov 1, 2012
  18. Harry3

    Harry3 Chuki

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    hahahahaha i havnt got a fucking clue mate I just picked a number out the air :teeth: awesome to know I was close-ish :D
     
  19. mistasfx

    mistasfx MISTA SFX

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    meeeehhhhhh lol

    u made me go over it again and again
     
  20. Harry3

    Harry3 Chuki

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    hahaha sorry, I may be a nerd but Im awful at maths!