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  • I get that after a big night on the pharmies.
    two nurofen plus, a JD and coke and a reefer normally sorts me out.

    No alcohol, but have codiene and morphine

  • pm'd

  • Well the itchy teeth are still here and now the gums ache too they are really annoying. Supposed it due to the anesthetic and nothing seems to make it go away.

    Any ideas what to do to make it go away

  • Teething gel.

  • pm'd

    hahaha

  • Teething gel.

    Tried it on the teeth and on certain areas of gums, I can't reach certain areas of gum as I almost pass out with pain.

  • Another numbing ingredient for the mouth is licorice tea. Another suggestion, try mixing teething gel with watch and gargling?

  • Where's the thread that's all about positive experiences in bike shops?

    I wish to commend Tomasz in Cycle Surgery Holborn for being utterly sound.

  • ta very much!

  • More spelling questions as neither google or my spell check seem able to help me.

    Ironically the word I wish to spell is idiotcity'', as init was my own idiotcity which led me to this siltation''.

    Yes I am a fucking idiot.

    Thank you.

  • idiocy

  • Thanks Balki, did you get my pm? Up for doing the wheel later?

  • Hey mate... yeah, I replied via PM? Hmmmm....

    Would be great if you could sort it for me. Are you suggesting doing it tonight?

  • where do you go to get your lego ? am looking for simple stuff like they had back in the day not the electronics degree level kit ?

    simple 4'ers 6'ers and 8'ers

  • Ebay is always good.

  • where do you go to get your lego ? am looking for simple stuff like they had back in the day not the electronics degree level kit ?

    simple 4'ers 6'ers and 8'ers

    My dad made me a great big wooden box for my lego, with a door-hinged lid and leather strap to hold it open. All painted red with my name on it in white hand-written letters. It was FULL of old Lego, all different ages, many with chewed corners. You had to dip your hand in and do a big sweep to find bits - sounded so loud, bit like a wave breaking. Would love to know where that is now, but it was lost years ago.

  • Full to the brim with Danish plastic win.

    There's a slogan if ever I heard one.

    New Lego bin, full to the brim with Danish plastic win!

  • Our Lego was in a cardboard box that went on the seat between me and my brother on long car journeys. Those DVD players can't be anywhere near as good.

  • no

  • What is the air-speed velocity of an unladen swallow?

    European of course.

  • In a twin charged system is it better to vent the supercharger airflow to atmosphere when the turbocharger comes on boost, or bypass the supercharger and remove it's parasitic drag on the crank with an electromagnetic clutch (as in the Eaton superchargers found in Merc C class)?

  • What is the air-speed velocity of an unladen swallow?

    European of course.

    A 54-year survey of 26,285 European Swallows captured and released by the Avian Demography Unit of the University of Capetown finds that the average adult European swallow has a wing length of 12.2 cm and a body mass of 20.3 grams.
    Because wing beat frequency and wing amplitude both scale with body mass, and flight kinematic data is available for at least 22 other bird species, it should be possible to estimate the frequency (f ) and amplitude (A) of the European Swallow by a comparison with similar species. With those two numbers, it will be possible to estimate airspeed (U).**
    **
    **[/B]By comparing the European Swallow with bird species of similar body mass, we can estimate that the swallow beats its wings 18 times a second with an amplitude of 18 cm:

            Species     Body mass   Frequency   Amplitude       Zebra Finch     13 g    27 Hz   11 cm       European Swallow    20 g    ≈ 18 Hz?  ≈ 18 cm?      Downy Woodpecker    27 g    14 Hz   29 cm       Budgerigar  34 g    14 Hz   15 cm       Note that even the tiny Zebra Finch flaps its wings no more than 27 times a second while cruising. 
    

    If we ignore body mass and look only at bird species with a similar wingspan, we can estimate an average frequency of 14 beats per second and an amplitude of 23 cm:

        Species     Wingspan    Frequency   Amplitude       Budgerigar  27 cm   14 Hz   15 cm       European Swallow    ≈ 28–30 cm    ≈ 14 Hz?  ≈ 23 cm?      Downy Woodpecker    31 cm   14 Hz   29 cm       European Starling   35 cm   14 Hz   26 cm      By averaging all 6 values, we can estimate that an average European Swallow flies at cruising speed with a frequency of roughly 15 beats per second, and an amplitude of roughly 22 cm. 
    [B]**
    

    For a European Swallow flying with an estimated wingbeat amplitude of 24 cm, the predicted pattern of cruising flight ranges from a Strouhal number (St) of 0.2:

        ![](http://www.style.org/unladenswallow/images/swallow_st2.gif)         ... to a less efficient 0.4: 
            ![](http://www.style.org/unladenswallow/images/swallow_st4.gif)        If the first diagram (St = 0.2) is accurate, then the cruising speed of the European Swallow would be roughly 16 meters per second (15 beats per second * 1.1 meters per beat). If the second diagram (St = 0.4) is accurate, then the cruising speed of the European Swallow would be closer to 8 meters per second (15 beats per second * 0.55 meters per beat). 
    

    If we settle on an intermediate Strouhal value of 0.3:

            ![](http://www.style.org/unladenswallow/images/swallow_st3.gif)        We can estimate the airspeed of the European Swallow to be roughly 11 meters per second (15 beats per second * 0.73 meters per beat). 
    
    
    
       Airspeed can also be predicted using a published formula. By inverting this midpoint Strouhal ratio of 0.3 (*f*A/U ≈ 0.3), Graham K. Taylor et al. show that as a rule of thumb, the speed of a flying animal is roughly 3 times frequency times amplitude (U ≈ 3*f*A).[5](http://www.style.org/unladenswallow/#5) 
    

    We now need only plug in the numbers:

    [INDENT] U ≈ 3*f*A
    f ≈ 15 (beats per second)
    A ≈ 0.22 (meters per beat)
    U ≈ 3*15*0.22 ≈ 9.9 [/INDENT] ... to estimate that the airspeed velocity of an unladen European Swallow is 10 meters per second.**
    **
    **
    **
    **[/B]An actual study of two European Swallows flying in a low-turbulence wind tunnel in Lund, Sweden, shows that swallows flap their wings much slower than my estimate, at only 7–9 beats per second:

          [INDENT] “Compared with other species of similar size, the swallow has quite low wingbeat frequency and relatively long wings.” [7](http://www.style.org/unladenswallow/#7) [/INDENT]  The maximum speed the birds could maintain was 13–14 meters per second, and although the Lund study does not discuss cruising flight in particular, the most efficient flapping (7 beats per second) occurred at an airspeed in the range of 8–11 meters per second, with an amplitude of 90–100° (17–19 cm).[B]
    

    **
    **
    **
    **[/B]Averaging the above numbers and plugging them in to the Strouhal equation for cruising flight (*f*A/U = 7 beats per second * 0.18 meters per beat / 9.5 meters per second) yields a Strouhal number of roughly 0.13:

                ![](http://www.style.org/unladenswallow/images/swallow_st13.gif)        ... indicating a surprisingly efficient flight pattern falling well below the expected range of 0.2–0.4. 
    

    Although a definitive answer would of course require further measurements, published species-wide averages of wing length and body mass, initial Strouhal estimates based on those averages and cross-species comparisons, the Lund wind tunnel study of birds flying at a range of speeds, and revised Strouhal numbers based on that study all lead me to estimate that the average cruising airspeed velocity of an unladen European Swallow is roughly [B]11 meters per second**, or 24 miles an hour.

  • ^ Repped...

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Any question answered...

Posted by Avatar for carson @carson

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