Comparing Two Balls' Heights: A Physics Problem

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The discussion focuses on a physics problem involving two balls with different initial speeds and heights. The blue ball is thrown upward with an initial speed of 23.5 m/s from 0.9 meters, while the red ball is thrown downward with an initial speed of 11.9 m/s from 31.4 meters, 2.9 seconds later. The gravitational acceleration for both balls is 9.81 m/s². Participants are asked to derive equations for the heights of both balls over time and determine the height of the red ball 3.77 seconds after the blue ball is thrown, as well as the time when both balls are at the same height. The discussion emphasizes setting up the correct equations to solve these questions effectively.
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A blue ball is thrown upward with an initial speed of 23.5 m/s, from a height of 0.9 meters above the ground. 2.9 seconds after the blue ball is thrown, a red ball is thrown down with an initial speed of 11.9 m/s from a height of 31.4 meters above the ground. The force of gravity due to the Earth results in the balls each having a constant downward acceleration of 9.81 m/s^2.

The Two questions are the following:

What is the height of the red ball 3.77 seconds after the blue ball is thrown?

and

How long after the blue ball is thrown are the two balls in the air at the same height?

Thanks for help much appreciated.
 
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Can you set up the equation to describe the blue ball?

Then set up a similar equation for the red ball but you will have to shift the time coordinate for the red ball by 2.9 seconds. From there it should be easy.
 


Got it thanks :)
 
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