WEBVTT

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Here is the problem: A projectile is launched at 15 m/s at 0° from a height of 20 m. Find its time of flight, range and maximum height.

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Treat horizontal and vertical motion separately: constant velocity horizontally, constant downward acceleration g vertically, ignoring air resistance.

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Split the launch velocity into components.

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Time to the highest point. The launch is level or downward, so the launch point is the highest point.

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Maximum height.

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Time of flight (land at height 0).

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Horizontal range.

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Impact velocity.

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So the answer is Time of flight approximately 2.0192751 s; range approximately 30.289127 m; maximum height approximately 20 m; impact speed approximately 24.847535 m/s.

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Without air resistance the horizontal velocity never changes, while the vertical velocity falls by g every second. The flight ends when the height returns to zero.

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Energy check: v squared at impact equals 617.4 and v₀ squared plus 2gh₀ equals 617.4 (equal).