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Homework Help: Conversion methods

  1. Sep 15, 2007 #1
    cant get around this problem: convert 40km/h to ft/sec.
     
  2. jcsd
  3. Sep 15, 2007 #2

    cristo

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    Well, the units are [tex]\frac{km}{h}[/tex] so you need to convert the km to feet and hours to seconds, then plug them into that fraction.
     
  4. Sep 15, 2007 #3

    Danger

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    If you need help in converting the units, Google has a built-in conversion programme. In the search field, you can just enter something like 'how many feet in a kilometer' and it will tell you.
    There's also a really awesome converter on line, which someone here in PF was kind enough to provide a link to. Unfortunately, that's on my iBook bookmark list and I'm now on the PC at work. If it doesn't show up before, I'll find it when I get home and post it here.
     
  5. Sep 15, 2007 #4
    (40km/1h)x(1mile/1.609344km)=24.85484769m/h ??
     
  6. Sep 15, 2007 #5
    aw thats cool. atleast i have an answer to check my work by thanx!
     
  7. Sep 15, 2007 #6

    cristo

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    Yes, that's correct. Although, a quicker way would be to write 40km in metres, then convert metres to feet (since, I imagine, you know how many metres in a km, but not how many feet in a mile). Then do the same for the time.
     
  8. Sep 15, 2007 #7
    so 24.85484769 X 5280 = 131,233.59580ft/hr. ?
     
  9. Sep 15, 2007 #8
    and that number divided by 3600sec/hr = 36.45377----ft/sec.
     
  10. Sep 15, 2007 #9

    cristo

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    Yup, that's correct (but I guess you checked that using google: "40 km/h in feet/s")
     
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