
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!

Angle of Elevation and Depression

  1. Jul 30, 2015 #1
    A man is standing on a 48.5 building and is looking on a second building. The angle of depression of the top and foot of the second building is 50 degrees and 80 degrees, respectively. What is the height of the second building? The height from the foot to the eye of the man is 1.5 m.

    Hello guys!
    I tried answering this problem and I kind of a lost of what to do here. This is my illustration, I don't know if I drew the correct illustration. Any help for answering this hard question (for me lol) will be appreciated. Thank you and God bless!!
  2. jcsd
  3. Jul 30, 2015 #2
    What have you tried till now ?
  4. Jul 30, 2015 #3
    First I tried getting it using soh cah toa which I got really lost because I don't know how will I apply soh cah toa here.
    I have the angle but I don't know how to use the 48.5 and 1.5.
  5. Jul 30, 2015 #4
    What is ' soh cah toa ' ?
  6. Jul 30, 2015 #5
    Uhhh like this?

  7. Jul 30, 2015 #6
    Take distance between the two buildings as , say , d .

    Write the formula for tan twice . Eliminate d . Solve .

    I haven't heard of that before .
  8. Jul 30, 2015 #7
    Okay sir can you be a little specific, I'm getting into it. How do I take the distance between the two buildings sir?
  9. Jul 30, 2015 #8
    There is some unknown distance between the buildings . Let this be a variable d , or any other of your liking .

    Let difference in height of buildings be h .
    Now write tan from the top of the second building . Then from the bottom .

    Thus find h .
  10. Jul 30, 2015 #9
    Okay will update you later sir. Thankyou for the help!! Hoping I can get it this time.
  11. Jul 31, 2015 #10
    Got it sir! (pls excuse my bad hand writing lol) Thankyou for assisting me. Cheers mate