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Gravity Problem?

  1. Sep 17, 2010 #1
    Gravity Problem??

    1. The problem statement, all variables and given/known data
    1) A college student wants to toss a textbook to his roommate who is leaning out the window directly above him. He throws the book up with a velocity of 8.0m/s. The roommate catches the book while it is traveling 3.0m/s upward.
    a.) How long was the book in the air?
    b)How far did the book travel in the upward direction?

    2.) During the 2004 Summer Olympics Emilie Heymans and Blythe Hartley won Canada's first meals with 10.0m synchronized dive. If the divers' heads entered the water 55km/h and each diver was 1.6m tall, at what speed did they initiate their dive?

    2. Relevant equations
    Not Sure But Gravity?

    3. The attempt at a solution

    I was supposed to be their for the lesson but i couldn't because i had a doctors appointment, and i am completely clueless on this lesson and i don't want to be left behind in physics. So far im understanding it but i don't know what equations they're asking for in these questions. I'm guessing though we have to include gravity.
  2. jcsd
  3. Sep 17, 2010 #2
    Re: Gravity Problem??

    1.1 the book was thrown upward with an initial speed of 8 m/s, but after the thrower lost contact it lost speed at a rate of 9.81 m/s per second. So how many seconds do you think the book has been travelling up when it has reached a speed of 3 m/s?
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