Is My Calculation of 81.48 Meters in Projectile Motion Correct?

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Homework Help Overview

The discussion revolves around a projectile motion problem where the original poster questions the accuracy of their calculated height of 81.48 meters. The context involves analyzing the trajectory of a projectile launched at a 45-degree angle.

Discussion Character

  • Exploratory, Conceptual clarification, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the organization of the original poster's work and suggest breaking the problem into segments. There is a focus on the relationship between the horizontal and vertical components of velocity due to the launch angle. Questions are raised about the validity of the formula used and the importance of working symbolically before substituting numerical values.

Discussion Status

The discussion is ongoing, with participants providing feedback on the original poster's approach and suggesting improvements in problem-solving techniques. There is no explicit consensus yet, but guidance has been offered regarding the organization of work and the method of tackling the problem.

Contextual Notes

Participants note that the formula referenced by the original poster may not apply due to the conditions of the problem, emphasizing the need for clarity in the setup and assumptions made.

Kingyou123
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Homework Statement


Check for first upload

Homework Equations


I wrote them down in my attempt at a solution

The Attempt at a Solution


Second upload, 81.48 meters high seems really wrong to me...
 

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As an aside, looking at your work is hard to follow. I think you could work on your organizational skills and hold off a bit more before plugging in numbers.

Your height at 95 meters downrange is incorrect, why don't we break this problem into segments. What are you trying to find initially to solve this problem?
 
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Since the launch angle is 45 degrees, you can make use of the fact that vx = vy for the components of initial velocity.
 
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The formula you quote at the end of line 6 (d= etc.) is only valid when there is no net vertical displacement.
I heartily endorse Student100's advice to avoid plugging in numbers until the very end. Work the algebra entirely symbolically. Much easier to follow, to check for dimensional consistency, to spot algebraic mistakes...
 
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