Results 1 to 4 of 4
Like Tree1Thanks
  • 1 Post By MarkFL

Math Help - diffrentiate help s(t) = 200t - 4tsquared

  1. #1
    Newbie
    Joined
    Jan 2013
    From
    galway
    Posts
    17

    diffrentiate help s(t) = 200t - 4tsquared

    Need hep with a problem , im not very good at calculus but ive taken a stab probly wrongly at most of them
    .
    As soon as it touchesdown , an airoplane applies its brakes. The distance s which the plane travles has travelled alon the runway at any subsequent time t is given by s(t) = 200t - 4t2

    1) find distance travelled after 10 seconds

    so do i just sub in 10 every tine ther is t i.e. 200(10) - 4(10)squared?

    2)the planes speed at any time t?

    do i just diffreenciate to
    200 - 8t ?

    3)the speed fo the plane at t=10s
    i sub 10 into above formula for t?


    4)the planes speed as it touches down

    not sure about this

    5)the time at which the plane comes to rest

    plane come to rest when t = 0 ???

    6)the distance the plane has travelled along the runway when it stops

    again no idea on this one
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor MarkFL's Avatar
    Joined
    Dec 2011
    From
    St. Augustine, FL.
    Posts
    1,988
    Thanks
    734

    Re: diffrentiate help s(t) = 200t - 4tsquared

    1.) Yes, find s(10).

    2.) Yes, v(t)=s'(t).

    3.) Yes, find v(10).

    4.) Find v(0).

    5.) Solve v(t)=0 for t.

    6.) Use the time t=t_f from part 5.) and find s(t_f).
    Thanks from ronanbrowne88
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Jan 2013
    From
    galway
    Posts
    17

    Re: diffrentiate help s(t) = 200t - 4tsquared

    great thanks for clearing that up,
    got them all except last one cant seeem to figure it out
    , t=t_f ? not framilar with that, what is the f stand for?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor MarkFL's Avatar
    Joined
    Dec 2011
    From
    St. Augustine, FL.
    Posts
    1,988
    Thanks
    734

    Re: diffrentiate help s(t) = 200t - 4tsquared

    I just used a subscript of f on t to denote the "final" time, i.e., the time at which the plane has come to a stop.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 11
    Last Post: May 9th 2010, 09:55 AM
  2. If the moment generating of X is M (t) = exp(100t + 200t^2)
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: November 2nd 2009, 11:00 AM
  3. how to diffrentiate a fraction?
    Posted in the Calculus Forum
    Replies: 1
    Last Post: August 17th 2009, 08:59 AM

Search Tags


/mathhelpforum @mathhelpforum