Hello, according to this page on how gravity works according to the FE model :
http://www.theflatearthsociety.org/tiki/tiki-index.php?page=GravityIn the Flat Earth model, 'gravity', rather than being a force, is the upward acceleration of the Earth. The Earth always accelerates upward at 1g, which is equivalent to the gravitational acceleration in the Round Earth model.
I know that not all flat earthers agree on this but I just wanted to investigate this idea. Anyway I thought : since the Earth is accelerating at a constant 1g, then calculating its speed should be easy. We only need to know the age of the Earth. I know that not all flat earthers agree on this either. Since FE is often linked with religion and creationism, I've seen 6000 years (according to the Bible) often accepted in FE debates.
Now, maybe calculating a speed from acceleration and time isn't everyone's cup of tea. In this case it's very simple because the acceleration is constant. Let's assume the Earth was created 6000 years ago, that's really the minimum we can go to. Let's also assume it starts with a speed of 0 when it's created, that's also the minimum we can go to. Then it starts accelerating constantly at the rate of 1g. That means each second since its creation it gains an additional 9.8 meters / second. All you have to do is multiply the number of seconds by 9.8 to find its speed in meters per second.
So let's calculate 6000 years in seconds :
60 * 60 * 24 * 365 * 6000 = 189 216 000 000 seconds
Again this is a lower estimate, for the sake of simplicity I didn't account for leap years or anything fancy. Let's multiply that by 9.8 to find the speed in meters per second :
189 216 000 000 * 9.8 = 1 854 316 800 000 meters / second
Or roughly 190 million kilometers per second.
So that gives us 6 675 billion kilometers per hour, or 4 150 billion miles per hour.
Here's my conclusion. I often see flat earthers use this argument : "NASA tells us that the Earth rotates at a speed of over 1000 miles/hour at the equator, that it orbits the Sun at 67 000 miles/hour, and that the Sun shoots through the galaxy at 500 000 miles/hour, for a wooping total of nearly 570 000 miles/hour".
They often use these numbers with emphasis to show that it cannot be, simply because we don't feel any of it. Well the truth is that according to the FE model, the Earth goes way way way faster. Just thought flat earthers needed to know this.