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!

Another simple velocity question.

  1. Oct 3, 2007 #1
    [SOLVED] Another simple velocity question.

    "Juanita left on a walk 45 min ago. She is travelling at 4.5 km/h. How fast must you travel to catch up to her in 1.0h"?

    Juanita t=45 min v=4.5 km/h
    d=vt = (4.5km/h)(0.75h) = 3.375 km

    Me -
    v=d/t = (3.375km)/1.0h = 3.4 km/h

    I must travel at 3.4 km/h to catch up to her in 1 hour.
    Correct?
     
  2. jcsd
  3. Oct 3, 2007 #2
    for the 1 hour you chased Jua... she must also have traveled.
     
  4. Oct 4, 2007 #3
    REVISION to simple velocity Q.

    ***REVISION***
    Juanita left on a walk 45 min ago. She is traveling at 4.5 km/h. How fast must you travel to catch up to her in 1.0h"?

    Juanita t=45 min +1.0h min v=4.5 km/h
    d=vt = (4.5km/h)(1.75h) = 7.8 km

    Me -
    v=d/t = (7.8km/1.0h) = 7.8 km/h

    I must travel at 7.8 km/h to catch up to her in 1 hour.

    Is it this? For some reason the answer still doesn't seem right...
     
  5. Oct 4, 2007 #4

    learningphysics

    User Avatar
    Homework Helper

    You aren't rounding your answer properly. It should be 7.875km/h, which is 7.9km/h when rounded to 2 sig.figs.
     
  6. Oct 4, 2007 #5
    So then I did get the right answer, just didn't round properly, right? Thanks!
     
  7. Oct 4, 2007 #6

    learningphysics

    User Avatar
    Homework Helper

    yeah. no prob. But why did you think your answer was wrong?
     
  8. Oct 4, 2007 #7
    I don't know, I just thought it was too easy to be the right answer... does that make sense? lol

    ps. how do you close a thread when a question is solved?
     
  9. Oct 4, 2007 #8

    learningphysics

    User Avatar
    Homework Helper

    Yeah, I understand that. :smile:

    I'll mark the thread as "SOLVED". It won't close it, but that's ok.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Another simple velocity question.
Loading...