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Constant Acceleration Problems

  1. Jan 4, 2009 #1
    Hey i do not know how to do ANY of these problems i tried using equations and plugged it in and i don't know how to do it please help....

    1. The problem statement, all variables and given/known data

    1. A golf ball is hit with a velocity of 30 m/s at a 28 Degree angle. what is the max height the ball reaches?

    2. A Ball is thrown off a cliff horizontally off a cliff at a velocity of 43 m/s if the ball lands 145m from the base of the cliff how long does it take the ball to reach the ground.

    3. A foot ball is projected on a flat surface at a 32 degree angle. If the ball lands 45m from where it started, what is the balls initial velocity

    4. A Ball is thrown upward off a cliff at angle of 40degrees horizontally and with a velocity of 35m/s. If it takes 12.5s for the ball to reach the bottom of the cliff, how high is the cliff.

    5 A Ball is projected off the top of a 180m high cliff with a velocity of 24 m/s and an angle of 34Degrees. How far from the bottom of the cliff is the ball after 4.2s.

    2. Relevant equations


    Range = Dx = (initial Velocity)^2 (Sin 2 (theta)) / lgl

    d = (initial velocity)(t) + 1/2 (g)(t)^2

    d= 1/2 (Initial Velocity + Final Velocity)(t)

    Final Velocity = Initial Velocity + g(t)

    (Final Velocity)^2 = (Initial velocity)^2 + 2(g)(d)

    3. The attempt at a solution

    I attempted all the problems but got wierd decimal numbers and it didnt LOOK right too much to type for 5 questions... however can someone just tell me which equation to use for each and then if i used it, i will understand if its correct or not... thanks.
  2. jcsd
  3. Jan 4, 2009 #2


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    Homework Helper

    1)Take the vertical component of the velocity of the ball. When it reaches the maximum height its final velocity is zero. Use fifth equation from your list to find the maximum height.
    2)When a Ball is thrown off a cliff horizontally, its velocity remains constant in that direction. So the distance /velocity will give you the answer.
    3)You can use the first formula for this problem.
    4. Take vertical component of the velocity, and use second formula with proper sign to initial velocity and g.
    5)From the above clues, try to solve this problem.
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