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!

Help with Vector Excel lab

  1. Sep 18, 2004 #1
    I have to do this problem using Microsoft Excel.

    A motorboat leaves the dock and travels in a direction 15 degrees East of North for 20 minutes at a constant speed of 20 miles/hour. At that point the boat abruptly changes its direction to 20 degrees South of West and its speed to 25 miles/hour and continues on that new course for 35 minutes. Assuming that the lake is still, calculate the answers to the following questions:
    (a) What is the boat's displacement (magnitude and direction) after 55 minutes?
    (b) What is the total distance travelled by the boat?
    (c) What is the boat's average velocity (magnitude and direction) after 55 minutes?
    (d) What is the boat's average speed after 55 minutes?

    First leg: (15 degrees East of North)
    Time ? minutes
    Speed ? miles/hr
    Magnitude of displacement #1 ? miles

    Second leg: (20 degrees South of West)
    Time ? minutes
    Speed ? miles/hr
    Magnitude of displacement #2 ? miles

    Choose the +x coordinate as East and the +y coordinate as North.
    Find the x and y components of the two displacement vectors.
    x-comp. y-comp.
    displacement #1 ? ?
    displacement #2 ? ?
    total displacement ? ?
    magnitude direction
    total displacement ? ?
    total distance travelled ?
    average velocity ? ?
    average speed ?

    Obviously each area with a ? needs data or an equation filled in there. If some people can guide me through this, it'd be greatly appreciated.
     
  2. jcsd
  3. Sep 18, 2004 #2
    I guess what I don't understand in the first part is, they want the magnitude of displacement 1. That'd just be d=tv, but t is in minutes, and v is in miles/hr, and you're supposed to keep the answer in miles/hr. When I enter the formula into the "Magnitude of displacement #1 ? miles" part, should I just enter =(11/12)*B16? 11/12 would be the 55 minutes as a fraction of 1 hour, and the B16 is just the cell where the 20 miles/hr is.

    *Edit: neglect this. I was using the 11/12 incorrectly, I meant 1/3 in the first part*
     
    Last edited: Sep 18, 2004
  4. Sep 18, 2004 #3
    Here's what I got so far

    First leg: (15 degrees East of North)
    Time 20 minutes
    Speed 20 miles/hr
    Magnitude of displacement #1 6.6666667 miles

    Second leg: (20 degrees South of West)
    Time 35 minutes
    Speed 25 miles/hr
    Magnitude of displacement #2 14.58333333 miles

    Choose the +x coordinate as East and the +y coordinate as North.
    Find the x and y components of the two displacement vectors.

    x-comp, y-comp
    displacement #1: 6.44, 1.73
    displacement #2: 13.70, 4.99
    total displacement: 20.14, 6.71
    magnitude
    total displacement: 21.23
     
  5. Sep 18, 2004 #4
    "total displacement: 21.23"

    Then to get the direction, I took the inverse tangent of (6.71/20.14) and got 18.4 degrees.

    Can anyone verify what I have so far?

    Now how should I go about the total distance, average velocity, and average speed?
     
  6. Sep 19, 2004 #5
    bump, come on
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Help with Vector Excel lab
  1. Lab help (Replies: 2)

Loading...