The Coriolis effect does not determine which direction water swirls down sinks or toilets because the effect is tiny & masked by other, much stronger factors. However, by eliminating these other factors, water will consistently swirl counterclockwise well North of the Equator and clockwise well South. This phenomenon proves Earth is a rotating sphere.
Flat-Earthers noticed the myth about water swirling down sinks & use it to dismiss the Coriolis effect. In reality, it is only a myth because other factors mask the Coriolis effect. Removing these factors lets us observe the water swirling from the Coriolis effect alone.
Continue reading “Detecting Earth’s Rotation by Draining Water”
It is a myth that the Coriolis force determines which direction water spirals down drains in everyday cases. The Coriolis force is too small in such cases. Sadly, charlatans have been using it as a tourist trap near the Equator, exploiting unsuspecting tourists.
Flat-Earthers realized the Coriolis tourist trap was just a parlor trick & used it to dismiss the Coriolis effect. In reality, scientists have been debunking this myth all the time. It is flat-Earthers who were duped into thinking it is a genuine scientific argument.
Continue reading “Coriolis Tourist Trap”
Chinese astronauts performed science demonstrations at the Tiangong Space Station. One of these demonstrations involves a glass of water and a ping-pong ball. Flat-Earthers saw a photo of the glass of water from the set, and they used it to discredit spaceflight. They claim that if it is really in space, then the water and glass should float.
In reality, the glass was attached to the table, and the water stayed in the glass because of adhesion between the glass and water, not gravity. The surface of the water also bulges and is not level with the glass or the table, as expected in a microgravity environment.
The astronauts used the set to demonstrate buoyancy in space. They pushed a ping-pong ball into the water, and it did not float like on Earth. At the end of the demonstration, they detached the glass from the table and floated it with the water & the ping-pong ball still inside it, and everything behaved as it should in a microgravity environment.
Continue reading “Demonstration Using a Glass of Water at the Tiangong Space Station”
Ocean tides occur because the water flows from locations with a low tide to those with a high tide on the other side of the world. On the other hand, the world’s lakes are not interconnected, & therefore, no significant tides can occur.
Tides are much smaller in lakes, and flat-Earthers use them to discredit gravity. In reality, lakes are not connected. Water in a lake cannot flow to another on the other side of Earth and cannot cause a low tide to one & high tide to another.
Continue reading “Why No Significant Tides Occur on Lakes and Other Bodies of Water”
Earth’s gravity causes water’s surface to curve with the same radius as Earth’s. On glass with a diameter of 10 cm, Earth’s gravity causes the water to form a curvature of 0.00000002 cm, outside other factors like surface tension.
Flat-Earthers like to demand that we prove water curvature in a glass of water. In reality, whatever the container, the curvature of the water surface remains the same as Earth’s radius. On a glass of water, it will be too small to observe.
Continue reading “Glass of Water”
Turning Torso is a skyscraper in Malmö, Sweden, having a distinctive segmented shape & easy to recognize from far. From Copenhagen, Denmark, we can see its lower part is obscured more if we are farther because Earth is a sphere.
The building is close to the strait of Øresund. Copenhagen, Denmark, lies at the other side of the channel, only 15 km (9 miles) away from Malmö. Turning Torso has a distinctive segmented shape that is easy to recognize from far. And more importantly, for our purposes, its segmented form makes it easy to judge its height from far.
Continue reading “Turning Torso Building, Malmö, Sweden”
The gravitational acceleration exerted by the mass of a wet, spinning tennis ball is too small compared to the centrifugal acceleration generated by its rotating motion. As a result, the water escapes away from the tennis ball, unlike Earth.
A wet spinning ball is a sphere, spinning & wet, like Earth. But the water goes away from the ball, unlike Earth. Flat Earthers use it to “disprove” spherical Earth. In reality, the magnitude of the involved accelerations in the two cases are different.
Continue reading “Wet, Spinning Tennis Ball False Analogy”
If Earth is a sphere, why is the surface of water always flat?
Due to Earth’s gravity, water seeks the lowest potential or as close as possible to the center of Earth. It forms a practically spherical surface centered on Earth’s center. The width of the surface in everyday cases is tiny compared to Earth’s radius. Thus, the water surface looks practically flat but not perfectly flat.
Continue reading “Curvature of Water Surface”
Refraction is the change in the direction of light due to the change in the medium’s refractive index traveled by the light. It is convenient to use water in a demonstration of refraction. But water alone is not the cause of refraction.
Flat-Earthers falsely claim that just because our atmosphere has water vapor in it, it will produce the same effect as any demonstration of refraction involving water. In reality, it requires far more reasoning than just that water is involved.
Continue reading “Refraction and Water”
An egg will generally sink in freshwater, but if we pour salt into the water and stir it, then the egg will start to float. The reason is that after salt is added, the density of water increases. However, the relationship between density and if the egg floats or sinks is not a direct causality.
Flat-Earthers claim that the phenomenon “proves” things fall because of density, and that gravity does not exist. In reality, the density of the water determines the magnitude of buoyancy the egg receives. If the buoyancy is higher than the weight of the egg, the egg will float, and vice versa.
Continue reading “Egg and Salt Water”
Gravity is the attraction between objects with mass. The higher the mass, the greater is the gravitational attraction. Gravity is not the result of the shapes of the objects.
Flat-Earthers like to perform the ball-and-water ‘experiment.’ They spray water to a ball, then observe the water does not stick to the ball the same way the ocean water curves over the surface of the Earth. They would wrongly conclude that “gravity does not exist.” Gravity does not come from the spherical shape of objects, Continue reading “The Ball and Water ‘Experiment’”
On many flights, they would give away leveling devices to all passengers for free, so that everyone would be able to observe the dip of the horizon and proves Earth is a sphere. And as a nice side effect, to quench our thirsts, too!
Such devices are called ‘bottled water’. Using these simple ‘instruments’ on a flight, we can demonstrate that Earth is a sphere.
Continue reading “Bottled Water: A Simple Device for Observing the Dip of the Horizon”
We often see flat-Earthers create a ‘miniaturized physical model’ of a real object and present them as ‘proof’ in support of flat-Earth and against spherical Earth. Their M.O. is to observe if the model remotely resembles the actual object in a particular way. If it does, then it is enough for them to conclude the model describe how the real object works.
Conversely, if a real object cannot be miniaturized and still have the same behavior as the original object, they would conclude that the behavior of the original object doesn’t exist.
They would wrongly call creating such models “doing an experiment”.
Continue reading “The so-called “Experiment” Done by Flat-Earthers”
As the Earth is spherical, the horizon is below the eye-level (or the astronomical horizon). The angle between the eye-level and the horizon is the dip of the horizon. The angle becomes larger as we go higher.
Flat-Earthers often claim that “the horizon always rises to eye-level”, and thus ‘proving’ the flat Earth claim. Despite their insistence to use a water level to ‘prove’ water is flat, the same device can be used to demonstrate the dip of the horizon, proving the water surface has curvature, and consistent with the spherical Earth model.
Continue reading “Water Level Demonstrates The Dip of the Horizon and Proves Earth’s Curvature”
Lake Pontchartrain is a lake in Louisiana, United States. There are power transmission lines about 24.27 km (15 mi) across this lake. They are practically straight, and each tower is uniform and has the same height, making these towers ideal for observing the curvature of the Earth.
They were first popularized by Soundly who presented evidence of Earth’s curvature using a series of photos and videos of the power lines in June 2017. As of now, the towers and other objects on the lake are probably the most popular Earth curvature tourism spot in the world.
Continue reading “Lake Pontchartrain Power Transmission Lines: Evidence of Earth’s Curvature”
Gravity is not the result of a particular shape of an object. It is caused by mass. All objects with mass exert gravity to each other. The larger the mass of an object, the greater the force of gravity.
On Earth, water forms a spherical surface which has the same center as the Earth. It applies to every surface of fluid which is under influence by Earth’s gravity, unaffected by another force. In a 10 cm wide container, the amount of curvature is only 0.0000002 mm. It is the reason the surface appears flat in small containers.
Continue reading “Surface of Water and Communicating Vessels”