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  • Projectile Motion: Finding the Launch Angle for Equal Range & Height
    You're asking about the launch angle that results in the horizontal range (x) and the maximum height (y) of a projectile being equal. Here's how to find that angle:

    Understanding the Equations

    * Horizontal Range (x): x = (v₀² * sin(2θ)) / g where:

    * v₀ is the initial velocity

    * θ is the launch angle

    * g is the acceleration due to gravity

    * Maximum Height (y): y = (v₀² * sin²(θ)) / (2g)

    Setting the Equations Equal

    We want to find the angle where x = y. Let's set the equations equal to each other:

    (v₀² * sin(2θ)) / g = (v₀² * sin²(θ)) / (2g)

    Simplifying

    1. Cancel out v₀² and g: sin(2θ) = (sin²(θ))/2

    2. Use the double-angle formula: sin(2θ) = 2sin(θ)cos(θ)

    3. Substitute: 2sin(θ)cos(θ) = (sin²(θ))/2

    4. Multiply both sides by 2: 4sin(θ)cos(θ) = sin²(θ)

    5. Divide both sides by sin(θ): 4cos(θ) = sin(θ)

    6. Solve for θ: tan(θ) = 4

    Finding the Angle

    Using a calculator or trigonometric tables, find the arctangent (tan⁻¹) of 4:

    θ ≈ 75.96°

    Important Note: There's another angle that satisfies this condition. Since the tangent function is periodic, there's a solution in the second quadrant as well. You can find this angle by adding 180° to the first angle:

    θ ≈ 75.96° + 180° ≈ 255.96°

    However: The second angle (255.96°) would result in a negative vertical displacement (the projectile would be going downwards), so it's not physically relevant in most projectile motion scenarios.

    Therefore, the launch angle where the horizontal and vertical distances are approximately equal is about 75.96°.

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