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!

Calculating when 2 points meet

  1. Jun 21, 2010 #1
    1. The problem statement, all variables and given/known data
    Runner A runs at 6.0m/s for 10s. Runner B accelerates from 4.0 m/s to 10.0 m/s steadily in 10s. How far does Runner A go in 10s? How far does Runner B go in 10s? At what time did Runner B pass Runner A if they were both at the same position at t=0?

    2. Relevant equations
    d= v*t, d = 1/2(v1+v2)*t

    3. The attempt at a solution

    Runner A:
    d = v*t
    d = (6.0m/s)(10s)
    d = 60m

    Runner B:
    d = 1/2(v1+v2)*t
    d = 1/2(4m/s+10m/s)*(10s)
    d = 1/2(14m/s)*(10s)
    d= 70m

    so therefore at 10s, Runner B has already surpassed Runner A by 10m. But how would you find when Runner B passed Runner A?


    Many thanks.
     
  2. jcsd
  3. Jun 21, 2010 #2
    Do you see that you want to find t such that vt = ½(v1+v2)t? How can you write v2 in terms of t?
     
  4. Jun 21, 2010 #3
    im sorry. i dont understand..
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Calculating when 2 points meet
Loading...