Do we (humans) live on the Earth or inside the Earth?
Human lives on earth, The Earth is divided into several layers which have distinct chemical and seismic properties. The crust varies considerably in thickness, it is thinner under the oceans, thicker under the continents. The inner core and crust are solid; the outer core and mantle layers are plastic or semi-fluid. The Earth's atmosphere is 77% nitrogen, 21% oxygen , with traces of argon, carbon dioxide and water. The oxygen in Earth's atmosphere is produced and maintained by biological processes. Without life there would be no free oxygen. Humans are among the many living organisms that lives on Earth and not inside the Earth. For more information go to Hollow Earth
Why can't helicopters just hover and let the earth rotate beneath it?
Ok, I didn’t read 71 answers. Just 10. So maybe I’m repeating something that has already been said. However:All answers I read were wrong. They are all stating that a helicopter is, in some absolute way, stationary when it hovers over a spot on the ground, and that no forces act upon it.Actually, it is not stationary relative to anything except the Earth’s surface at that specific latitude. Relative to, say, the center of the earth, it’s traveling in excess of 1 600 km/h around it, if it’s at the equator. And yes, a lot of force is at work.And the question asks why, as I understand it.Here’s why: The atmosphere is part of Earth as such, it just happens to be a bit less dense than all the other stuff. It whirls about a lot (just like the molten stuff under the Earth’s crust, but with less effort), due to the Coriolis effect, so there is wind. But let’s leave wind out of the equation for now.So, the force at work (when there is no wind) is the rotating atmosphere (which, again, is part of the rotating Earth). The helicopter could indeed stay stationary relative to something except the surface, such as the center of the earth, but it would have to be capable of an airspeed of around 1 600 km/h.So unless you consider - like someone did in another question - the F-35B a glorified helicopter, it doesn’t “hover” in the sense meant in the question (an F-35B could, though, flying due west).(unless the helicopter hovers at the true north or south pole, in which case both meanings of the word “hover” coincide)It is, however, not possible for a helicopter (not even an F-35 or even a Falcon Heavy, also a VTOL vehicle like a helicopter) to hover relative to the sun. Much less the Universe. But that’s another story.There are no absolutes.
On Earth, where do we live, inside or outside?
Many people think of humans as “land animals” — restricted to the 29% of the solid earth that interfaces with gas (atmospheric) portion of the earth — but that’s not quite right. While it’s true that we’re generally confined to the outer surface of the lithosphere (the crust), in reality we do not live IN the earth (land) like earthworms or rodents. Actually we live at the base of the atmosphere and more properly, should be called “sky animals”. Indeed, while we can survive for a number of days without water and perhaps weeks without food, we could not survive for more than a few minutes without ingesting oxygen from the atmosphere.Alternatively, given that the mass of the human body is 60 to 75% water, perhaps we should be called “sea animals”. The organs of the human body are literally bathed in fluids surrounded by an impervious coating (called “skin”). Our blood has many of the properties of seawater. Needless-to-say, we need water to survive.So, what are we? Land animals, sky animals, sea animals? I guess, all three of the earth’s physical states. As the saying goes: “We are the Earth”.
If the Earth is a globe, why is the horizon flat from an aeroplane?
I can demonstrate that the Earth is a sphere without even going on a plane. I just need to find a picture with few trees obstructing my view. I know, I’ll find a big hole in the ground to make things simple.This picture was taken on the North Rim of the Grand Canyon at approximately 8,200 feet (2500 meters) of elevation. Humphreys Peak at its highest is 12,637 feet (3,852 meters) in elevation with around 6,000 feet (1828 meters) of prominence. The South Rim of the Grand Canyon wavers around ~6,860 feet in elevation. If the Earth were flat, we would be able to clearly look down on the base of Humphreys Peak. This is obviously not the case.Humphreys is about 60 miles (96.5 kilometers) away from that position, well beyond the horizon distance. The base of Humphreys Peak is literally blocked from view by the curvature of the Earth.If you think the horizon is flat when you look out an airplane window, that’s because your eyes don’t have enough resolution to see the curvature. In fact, the very existence of a horizon at all means that the Earth is not flat. The horizon is the point where the Earth’s surface curves far enough away from a viewer that the surface is no longer visible.
Earth and sun.?
Neither. They both move around the center of gravity of the Sun-Earth System.( The Earth exerts a gravitational attraction on the Sun, just as the Sun does on Earth.)
If the earth is rotating at a high speed and we jump up, why doesn't the earth move below us at high speed?
Since other answers have correctly mentioned the atmosphere and such, let's take it out of the equation for the sake of argument and see what happens.In terms of the difference in the helicopter's path vs. the ground, let's look at what happens during one whole day as the Earth rotates. Assuming the helicopter can perform an ideal, vertical-acceleration-only hover, then the surface of the Earth and the helicopter have the same tangential speed as the Earth turns, due to conservation of momentum. But, since the helicopter is now a few feet (~1 meter) above the ground, the path the helicopter takes to go around the Earth during one day is now slightly longer as compared to the surface itself. The added circumference of that trip all the way around the Earth for the helicopter turns out be just 2 times Pi times the height above the ground. It takes the Earth just under 24 hours to rotate once on its axis, so the helicopter would have to move at an additional horizontal speed of maybe 18 feet (~5.5 meters) per 24 hours, or something like 0.00014 miles per hour (~0.00022 km/h) to stay directly over the same spot on the ground. This is such a negligible difference in horizontal speed that you don't notice it in any practical system.A real helicopter would deviate horizontally by a speed that is orders of magnitude more than that when it takes off anyway. And, of course, helicopters fly in the atmosphere, which is coupled to the ground. It's also fair to say that wind speed dominates any effects from conservation of momentum, as it's orders of magnitude larger, even at high altitudes. So, real aircraft worry about the difference in wind speed and direction vs. the ground, rather than orbital mechanics.
Is the weather warm or cold close to the equator? and why?
The temperatures at the equator are generally warmer than anywhere else. This is NOT because the equator is closest to the sun, despite popular belief. The sun is around 93 million miles away, the equator being a few thousand miles closer makes a negligible difference. The reason that the equator is warmer is that it recieves the highest intensity of sunlight, as the sun's rays are focused most on this area. If you travel north or south of the equator, the light is more spread out, as Earth is spherical (There is more energy per metre cubed reaching the equator than anywhere else) That is why it gets cooler the closer to the poles you get. This is all made more complicated by the atmosphere and oceans, but is essentially the governing factor.