1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Triangular numbers and v-t graph

  1. May 30, 2005 #1
    http://student.shcc.edu.hk/~s021107/phy.GIF

    Displacement=area under v-t graph = 150m

    using another concept,
    the acceleration is 0.75m^s-2, so the displacement at
    1s=0.75m
    2s=0.75*2m
    .
    .
    .
    20s=0.75*20m

    total displacement =sum of displacement of every second
    =0.75*(1+2+3+...+18+19+20)
    =157.5m
    Can you tell me wt's wrong here?
     
  2. jcsd
  3. May 30, 2005 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Your link isn't working, but I assume you are describing uniformly accelerated motion starting from rest.

    Since [itex]v = at[/itex]:

    At t = 0s, the speed is 0 m/s
    At t = 1s, the speed is 1*.75 = 0.75 m/s
    At t = 2s, the speed is 2*.75 = 1.5 m/s, .... etc.

    To find the displacement during each second, use [itex]\Delta d = v_{ave} \Delta t[/itex], where the average speed equals [itex]v_{ave} = (v_i + v_f)/2[/itex]. Add these displacements and you'll find that they total to 150m.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Triangular numbers and v-t graph
  1. V/T graph to P/T graph (Replies: 4)

Loading...