Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

S(t) for 100 cigarette smokers w/5 min cigarette/30 min

  1. Jul 21, 2011 #1


    User Avatar
    Gold Member

    100 cigarette smokers in sucession light up a cigarette each 5 minutes, so after 500 min
    all have lite up. Each cigarette lasts 5 min.
    During this time period and for an extended time , each smoker from time of last cigarette
    lites up every 30 min for a 5 min smoke.
    What would the function, S(t) be ?
    How many of the 100 are smoking at any time (t) ?

    If it was steady state it could be 5min * 100/30 min
    But maby it is periodic
  2. jcsd
  3. Jul 21, 2011 #2
  4. Jul 21, 2011 #3
    When does time start?
    You know, is t=0 when the first smoker lights up his cigarette?
    Or is it t=0 when time starts and THEN on the 5 min mark the first smoker lights up his cigarette?

    In the first case, you only need 495 minute until all 100 smokers light up their cigarettes.

    In any case, you need to plot one line per smoker that represent their smoking rate...if they all smoke at the same rate their slopes are the same, but they cross the x-axis at different points since they started to smoke at different times....

    ....then, you need to plot a vertical line at some point to help you figure out how many smokers are smoking at any given time...

    hope this helps.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook