Type 1 Projectile with an initial vertical velocity

AI Thread Summary
A tourist throws a peach pit horizontally from an elevator moving upward at 8.5 m/s, with the ground 17 m below. The equation of motion used is d = Vot + 1/2at², leading to the equation -17 = 8.5t - 4.9t². The correct approach involves rearranging this into a standard quadratic equation, 0 = 17 + 8.5t - 4.9t². The solution for time, t, is found using the quadratic formula, resulting in approximately 2.92 seconds. The discussion emphasizes the importance of recognizing when to apply the quadratic formula in projectile motion problems.
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A rude tourist throws a peach pit horizontally with a 7.0 m/s velocity out of an elevator cage. The ground is 17 m below. How long will it take for the pit to land if the elevator is moving upward at a constant 8.5 m/s velocity?



d=Vot + 1/2at2



My attempt that continuously doesn't work is:
-17=(8.5)(t)+1/2(-9.8)(t2)
-17=8.5t - 4.9t2


The answer is 2.92s.. I'm just not quite sure how to get there. Please show all the steps in your solution.. I'm drawing a blank on how to solve for t!



Thank you!
 
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0=17+8.5t-4.9t^2

Then use the quadratic equation to solve it
 
leachlife4 said:
0=17+8.5t-4.9t^2

Then use the quadratic equation to solve it

oh right! i forgot about the quadratic equation.. got it now! thanks!
 
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