# Earth's Shape - Laser Test

This is a depiction of an experiment which seeks to determine the approximate shape of the earth, based on what should be expected if it is curved with a radius of 3959 miles or if the surface is flat.

The X and Y axes are not on a 1:1 scale, so the image will look off-scale. This is to fit a 3 mile X-length in proportion to around a 20 foot Y-length (which is graphic only, and does not affect the math).
Slider on left determines the height (h) the laser pointer is set up.
Slider on right (green) determines the angle (α) up or down the laser is sitting.
Each vertical line to the right of the y-axis is a duo of measurements, each containing one calculation for the flat earth measurements and one for the curved earth measurement, as should be expected with no atmospheric refraction.
The tables in the upper-left most corner display these measurements and the difference between each measurement repsectively on the right, for the flat and curved scenarios.
In the "Graphics 2" window, on the right, the measurements from the other side are plotted to display whether the function made by the measurements is approximately linear or nonlinear, where the curved measures are plotted with green points and the flat measures are plotted with blue points.

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