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    I need help finding the velocity, V2, of a ball after it strikes a frictionless flat horizontal surface. I'm given that V1 (the launch velocity) = 10 m/s, and the ball is launched at an angle pi/4.

    I'm told that the vertical velocity of the ball at the instant of the bounce changes by a factor of 0.2, and there isn't any change in horizontal velocity.

    so far I've resolved the initial velocity to it's horizontal and vertical components using equations:
    V1y = V1*sin(pi/4)
    V1x = V1*cos(pi/4)

    however I don't know the next steps are to finding the velocity after it bounces.
    pls help (I've included a paint drawing of the problem)
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    (Original post by dila247)
    I need help finding the velocity, V2, of a ball after it strikes a frictionless flat horizontal surface. I'm given that V1 (the launch velocity) = 10 m/s, and the ball is launched at an angle pi/4.

    I'm told that the vertical velocity of the ball at the instant of the bounce changes by a factor of 0.2, and there isn't any change in horizontal velocity.

    so far I've resolved the initial velocity to it's horizontal and vertical components using equations:
    V1y = V1*sin(pi/4)
    V1x = V1*cos(pi/4)

    however I don't know the next steps are to finding the velocity after it bounces.
    pls help (I've included a paint drawing of the problem)
    Consider the vertical motion from v1: find the heigth of the ball from v1 to its maximum height (where v=0). After finding the height, you can find V2 using the value of the height found, its initial speed (which will be 0 from its maximum height), acceleration will be 9.8m/s.

    Do the same method to find the final velocity (V3) after it hits the ground a second time.
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    (Original post by dila247)
    I need help finding the velocity, V2, of a ball after it strikes a frictionless flat horizontal surface. I'm given that V1 (the launch velocity) = 10 m/s, and the ball is launched at an angle pi/4.

    I'm told that the vertical velocity of the ball at the instant of the bounce changes by a factor of 0.2, and there isn't any change in horizontal velocity.

    so far I've resolved the initial velocity to it's horizontal and vertical components using equations:
    V1y = V1*sin(pi/4)
    V1x = V1*cos(pi/4)

    however I don't know the next steps are to finding the velocity after it bounces.
    pls help (I've included a paint drawing of the problem)
    You are told that v_{1y} = (1/0.2)v_{2y} and also v_{1x} = v_{2x}.
    You should find the components of the new velocity and substitute.
    edit: 3 days old and we manage to post a minute apart.
 
 
 
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