Initial velocity of projectile given angle and max height

AI Thread Summary
A projectile launched at an angle of 43 degrees reached a maximum height of 2974 meters, prompting a discussion on calculating its initial speed. The relevant equation is Vy² = V0y² - 2g(y - y0), where at maximum height, the vertical velocity (Vy) is zero. The angle of launch is crucial, as it relates the initial speed (V0) to the vertical component (V0y) through the equation V0y = V0 sin(θ). Clarification on these relationships helped the original poster arrive at the correct answer. Understanding the connection between the angle and the vertical component was key to solving the problem.
ulfy01
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Homework Statement


A projectile was fired across level ground at an initial angle of 43.00 degrees above the horizontal. During its flight, it reached a maximum height of 2974 metres. What was the initial speed of this projectile?


Homework Equations



I assume that the correct equation to use is Vy2 = V0y² - 2g(y - y0).

The Attempt at a Solution



To be honest I'm not even sure how to go about it. Given the equation, I would rearrange for V0y² however that doesn't seem to work at all. I'm not even sure what the value of Vy has to be. I also suspect the angle comes into play, but I'm not sure what it can tell me. Any pointers greatly appreciated.
 
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Your method is correct.
At the top of the flight, there is no vertical component of velocity, so v_y = 0 there. You are also correct that the angle is involved. Indeed, v_o\sinθ= v_{oy} and it is this v_o that you are solving for.
 
You're a life savior. It's this vo sinθ= voy that I wasn't able to get to. I got the answer right. Thank you so much!
 
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