Throwing a ball upward on top of a building, find height of building

AI Thread Summary
To find the height of the building from which a rock is thrown upward at 24 m/s and strikes the ground at 43 m/s, the equations of motion are utilized. The problem can be approached by first determining the time of flight without needing to solve a quadratic equation. The key is to calculate the displacement using the initial and final velocities along with the acceleration due to gravity. The height of the building can then be derived from these calculations. Understanding the motion equations is essential for solving this type of physics problem effectively.
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Homework Statement


Please help me with this problem:
Rock is thrown straight up with a velocity of 24 m/s from the edge of a building. The rock is moving at 43 m/s when it strikes the ground. Acceleration is 9.8 m/s^2. How tall is the building?



I know it involves the equations of motion. I think the first step is solving for the time with the quadriatic eq.

Homework Equations




The Attempt at a Solution

 
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Figure out the time, then the displacement. Two different equations. You don't need to solve a quadratic equation.
 
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