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Homework Help: Hi 2 Every1! Can Some1 Plz Plaz Help Me?

  1. Jan 26, 2005 #1
    HI TO ALL, THIS IS SAIRA, I AM NEW HERE.
    I AM REALLY WORRIED AS I HAVE A PHYSICS ASSIGNMENT AND I AM REALLY STRUGGLING BECAUSE I MISSED ALOT OF LESSONS BECAUSE I WAS ILL.
    COULD SOME1 PLZ HELP ME WITH THESE PROBLEMS, I WILL BE EVER SO GRATEFUL!!!!!

    1. A boy throws a stone from the edge of a cliff with an initial speed V o at an angle of 30 degrees above the horizontal. When it hits the surface of a lake 22m below the top of the cliff, the stone is moving with a speed of 25 meter per second. What was its initial velocity?
     
  2. jcsd
  3. Jan 26, 2005 #2
    Don't worry, it's actually very simple. Remember that horizontal and vertical motion are independant of each other (i.e. the vertical motion is affected by gravity, whereas horizontal motion is constant- that is, if there is no friction).
    Split the initial and final speeds into their horizontal and vertical components.
     
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