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!

Can someone help me please

  1. Nov 4, 2007 #1
    The airspeed of a small plane is 200 km/h. The wind speed is 50.0 k/h from the west. Determine the velocity of the plane relative to ground if the pilot keeps the plane pointing to each of the following directions:
    a) [E] b) [W] c) [N] d) [N400E]

    I never learned this stuff but it is on my homework, can anyone give me formula to solve this problem please?..
  2. jcsd
  3. Nov 4, 2007 #2


    User Avatar

    Staff: Mentor

    This is a problem of vector addition.

    The 200 km/h is the magnitude airspeed (speed of plane relative to the air) and the problem gives 4 orientations, which then defines that vector, to which one then adds the velocity of the wind.

    Since the wind if from the west, it is moving toward the east, so take E as the + direction, and denote the unit vector as i. For the opposite direction, W, the vector would be -i. Similarly N would be +j or j and S would be -j.

    Take part a. The plane if flying E at 200 km/h with respect to the air, and the air is moving E at 50 km/h. Adding the two vectors, one gets 200 i + 50 i = 250 i, so the plane is moving 250 km/h due E.

    Now try the others.

    See this reference - http://hyperphysics.phy-astr.gsu.edu/hbase/airpw.html
  4. Nov 4, 2007 #3
    Thankyou very much sir
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?