5 experiments flat earthers ignore

Okay, the flat earth ignorance, not only is astounding, but also annoying, so I've compiled together 5 individual experiments flat earthers can use to prove to themselves earth is spheroid so they can stop posting this dumb shit.

1. With a sniper rifle and one bullet

The Coriolis effect is a result of the earth's rotation, which impacts objects (typically bullets) travelling over long distances (usually miles) by making them rotate. As such, one merely needs to fire a sniper rifle over a mile or more of terrain to see the effect in action. The Coriolis effect is specifically a result of rotation and wouldn't be possible on a flat earth.

https://www.washingtoncitypaper.com/columns/straight-dope/article/13039128/do-snipers-compensate-for-the-earthrsquos-rotation-what-the-coriolis

2. With an object filled with water and a plughole (and maybe a vacation to a country on the equator)

The Coriolis effect similarly causes rotation on the motion of things like water, which is why when bathwater goes down the plughole, it spins (contrary to popular belief, which hemisphere you're in doesn't dictate the direction, just by using your hands you can cause it to swirl either clockwise or counter-clockwise. The hemispheres just impart a spin).

If you travel to an equator country, go to the mid-line of the equator, and allow water out of a container out of a hole, you will see that the water actually doesn't spin (you can use matches or leaves to confirm this). You can then travel to either side of the equator to test the inverse. This wouldn't occur if earth was flat.

You can see this effect at the equator demonstrated here:

https://youtu.be/4IIVfoDuVIw?t=47

3. By attaching a camera to a high attitude balloon, launching it and reviewing the footage

Spaceflights are expensive, so the next best thing is just launching a high attitude balloon (with the appropriate permissions from your airspace regulator) with a camera with a GPS tracker on it (so you can find it after it plummets back to earth). That way you can be sure the recording hasn't been tampered with or been deceptively edited. Here's one example video to demo high altitude balloons are a thing (although you might want to mute the garbage music):

https://www.youtube.com/watch?v=3y0nHhFGXDo

4. With a compass and two magnets

Magnets are what's known as 'diapole' (dia meaning 'two': 'two poles'), they have a north pole, and a south pole, which you can prove to yourself by getting yourself two cheap store bought magnets and attracting/repelling them against each other on their different ends.

A compass is a device that always points to the magnetic 'north' pole. Given magnets are diapole (have two poles), it would be physically impossible for a flat earth to have both a north and south pole (because if the north pole is located in the centre, where is the south pole located?). A sphere solves this as it has a top and a bottom.


5. With two sticks

The way the Greeks proved to themselves earth was round was to use shadows from many miles apart and record the positions of the shadows. They then compared the differences in the positions of the shadows to work out the earth was round by factoring in the angles. Flat earthers could easily make use of two similarly sized sticks many hundreds of miles apart measuring the shadow at noon to confirm this experiment.

Business insider actually has a really good video explaining the basics of how it was done:
https://www.businessinsider.com/how-greek-eratosthenes-calculated-earth-circumference-2016-6?op=1