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    The question is a golfer hits the ball from ground level, on a horiontal surface, the intial velocity is 21ms at 60 degrees above the horizontal, find the max height, range and speed at its max height, The max height is 16.9m and the range is 39.4m

    If i have to find the speed at max height. I cant get the answer, I would think theres no acceleration so its just D/T, but im halfing the time, which i got at (3.71), but still cant get it right?
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    (Original post by SunDun111)
    The question is a golfer hits the ball from ground level, on a horiontal surface, the intial velocity is 21ms at 60 degrees above the horizontal, find the max height, range and speed at its max height, The max height is 16.9m and the range is 39.4m

    If i have to find the speed at max height. I cant get the answer, I would think theres no acceleration so its just D/T, but im halfing the time, which i got at (3.71), but still cant get it right?
    To find the max height you need to consider vertical motion.

    So there is acceleration due to gravity.
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    (Original post by notnek)
    To find the max height you need to consider vertical motion.

    So there is acceleration due to gravity.
    I found the max height, Im talking about the speed of it, I thought since its at its max, there is no acceleration at that point?
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    (Original post by SunDun111)
    I found the max height, Im talking about the speed of it, I thought since its at its max, there is no acceleration at that point?
    There is no (vertical) speed at the max height, but there is certainly acceleration.
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    (Original post by SunDun111)
    I found the max height, Im talking about the speed of it, I thought since its at its max, there is no acceleration at that point?
    For these questions you have to try to separate horizontal and vertical motion.

    Vertically, the ball as an inital speed and acceleration due to gravity.

    Horizontally, the ball has an initial speed and no acceleration.

    So the ball will continue to move at a constant horizontal speed throughout the motion. The height of the ball will not affect this.
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    (Original post by Zacken)
    There is no (vertical) speed at the max height, but there is certainly acceleration.
    (Original post by notnek)
    For these questions you have to try to separate horizontal and vertical motion.

    Vertically, the ball as an inital speed and acceleration due to gravity.

    Horizontally, the ball has an initial speed and no acceleration.

    So the ball will continue to move at a constant horizontal speed throughout the motion. The height of the ball will not affect this.
    I understand, but the question simply states

    'Find the speed of the ball at its maximum height' ?
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    (Original post by SunDun111)
    I understand, but the question simply states

    'Find the speed of the ball at its maximum height' ?
    At it's maximum height, what is the vertical speed of the ball?
    What is the horizontal speed of the ball?

    Hence, what is the speed at maximum height?
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    (Original post by SunDun111)
    I understand, but the question simply states

    'Find the speed of the ball at its maximum height' ?
    And we've told you that at the maximum height:

    (i) there is no vertical velocity
    (ii) there is horizontal velocity.

    And that:

    (i) Horizontal velocity is constant throughout the motion.

    So if you can find the initial horizontal velocity, the horizontal velocity at the max height will be the same.

    Now that you know both the horizontal velocity at the max height (constant initial one) and the vertical velocity (0), you can do

    sqrt(horizontal^2 + 0^2) = horizontal.
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    (Original post by SunDun111)
    I understand, but the question simply states

    'Find the speed of the ball at its maximum height' ?
    If you use what I said before:

    At it's maximum height the vertical velocity of the ball is 0.

    At it's maximum height, the horizontal velocity of the ball is the same as the horizontal velocity throughout the motion since there is no horizontal acceleration. So the horizontal vecloity is equal to the initial horizontal velocity.

    So what's the speed of the ball at the maximum height?
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    (Original post by Zacken)
    And we've told you that at the maximum height:

    (i) there is no vertical velocity
    (ii) there is horizontal velocity.

    And that:

    (i) Horizontal velocity is constant throughout the motion.

    So if you can find the initial horizontal velocity, the horizontal velocity at the max height will be the same.

    Now that you know both the horizontal velocity at the max height (constant initial one) and the vertical velocity (0), you can do

    sqrt(horizontal^2 + 0^2) = horizontal.
    (Original post by notnek)
    If you use what I said before:

    At it's maximum height the vertical velocity of the ball is 0.

    At it's maximum height, the horizontal velocity of the ball is the same as the horizontal velocity throughout the motion since there is no horizontal acceleration. So the horizontal vecloity is equal to the initial horizontal velocity.

    So what's the speed of the ball at the maximum height?
    (Original post by lerjj)
    At it's maximum height, what is the vertical speed of the ball?
    What is the horizontal speed of the ball?

    Hence, what is the speed at maximum height?
    figured it out, asif I didnt think about it properly haha
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    (Original post by SunDun111)
    figured it out, asif I didnt think about it properly haha
    Glad you understood!
 
 
 
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