Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Kinematics help

  1. Jan 27, 2005 #1
    if a plane is flying at 720 km/h and drops a bomb when it is 2000 m high what is the length of time the bomb was in the air?

    So Viinitial is 720 km/h and d is 2000 m , g is 9.8 and to solve for t would i use the formuladeltay = Videltat + 1/2adeltay t^2?
  2. jcsd
  3. Jan 27, 2005 #2
    the vertical and horizontal component are independent, the result is not related to how fast the plane travel horizontally
  4. Jan 27, 2005 #3
    delta x = viX dellta t
    2000 = 720 km/h (delta t)
    delta t = 2000m/ 720 km/h. Therefore the length of time the bomb was in the air is 2.7 seconds?
  5. Jan 27, 2005 #4

    Doc Al

    User Avatar

    Staff: Mentor

    This is the correct equation to use, but not the correct initial velocity. All you care about is the vertical motion (which, as vincentchan points out, has nothing to do with the horizontal speed of the plane), so what's the initial speed in the vertical direction?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook