Vertical Motion w/ constant acceleration

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SUMMARY

The discussion centers on a physics problem involving vertical motion with constant acceleration, specifically analyzing the motion of two balls: one thrown upwards and the other dropped from a height of 20.6 meters. The goal is to determine the initial speed required for the first ball to ensure both balls hit the ground simultaneously, despite the second ball being dropped 1.14 seconds later. Key equations utilized include vf^2 = v0^2 + 2ax, vf = v0 + at, and x = x0 + v0t + 1/2at^2, emphasizing the importance of time being equal for both objects during their descent.

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  • Understanding of kinematic equations in physics
  • Knowledge of constant acceleration concepts
  • Familiarity with initial velocity and final velocity definitions
  • Ability to solve quadratic equations
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  • Review kinematic equations for vertical motion in physics
  • Practice problems involving simultaneous motion of two objects
  • Explore the effects of initial velocity on projectile motion
  • Learn about free fall and its equations of motion
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Students studying physics, particularly those focusing on kinematics and vertical motion problems, as well as educators seeking to enhance their teaching methods in these topics.

cdlegendary
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Homework Statement



A ball is thrown straight up from the edge of the roof of a building. A second ball is dropped from the roof a time of 1.14 s later. You may ignore air resistance.

A.) If the height of the building is 20.6 m, what must the initial speed be of the first ball if both are to hit the ground at the same time?

Homework Equations



vf^2 = v0^2 + 2ax
vf = v0 + at
x = x0 + v0t + 1/2at^2

The Attempt at a Solution



I'm really not sure where to start. If someone could help me out I would greatly appreciate it.
 
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Focus on the last of your three equations. "t" has to be the same for both objects: the one that's dropped, and the one that's thrown up.
 
ideasrule said:
Focus on the last of your three equations. "t" has to be the same for both objects: the one that's dropped, and the one that's thrown up.

Hmm but wouldn't there be two unknowns for that equation? I tried setting the equation equal to itsel but it turned out kind of badly, haha...
 

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