How is the world spinning on its axis?

Question

I am 11, I love science. We know that the world is spinning on it's axis, but can you explain how it does that? And how come we don't feel the earth moving? If something is moving or spinning can't you feel it? Please give real answers. Thanks.

Answer 1

I like like to say that almost everything Arch Angel said is wrong. There IS frictions, and in fact, Earth's self rotation is slowing down. And that we ARE in constant acceleration since the Earth is rotating in a circular fashion. The reason we don't feel is because everything else around us is moving at the same speed with us. Pretend if the air will not move but stationary, and you rotate with the Earth, you'll feel the air rushing by you. It's all relative, you just don't feel it because everything is moving with you. Plus, there is the gravity to pull you in to counter the centrifugal force you might have experience from the Earth's rotation. In another word, you asked "if something is moving or or spinning can't you feel it?" You are referring why we are not feeling like we are "being thrown out" and it's because Earth's gravitation is pulling us in. Don't listen to Arch Angel, he's completely wrong.  

Answer 2

Any rotating object has something called "angular momentum". It is similar to linear momentum (mass times velocity), but has to do with rotational motion instead. Like linear momentum, it is conserved (never changes) unless something acts on that body with an external force. In other words, and object once rotating stays rotating unless acted up by an external torquing force.

Answer 3

First off, there is no real physical axis, like an axel or anything. The earth is just spinning like a basket ball can be spun. You notice that spot of top of the spinning basketball that seems to be standing almost still while the rest of the ball spins around that point? Tha'ts the axis.

The reason why we don't fly off or really feel it much is because gravity is stronger (way stronger) that the force of momentum that would have us fly off into space. See, when you spin that basket ball fast and create a strong force its all in realtion to the mass of the basketball. Relatively speaking, the earth is not spinning fast enough for momentum to overpower gravity.

As to why we can't feel it, again its because gravity is the strongest force around us. Regardless of the earth's spin, down is always down. I suppose if the earth was much smaller or spinning much much faster, you might experience some light-headedness.  

Answer 4

Those are excellent questions.  In fact, long ago, people thought the earth must NOT be moving since they couldn't feel it move.  They used that to argue against other people who said the earth is spinning.

Galileo was one of the first people to argue that moving could "feel" just the same as standing still.  Later, Isaac Newton improved on that theory.  He said that what you feel is not really motion, but CHANGES in motion.  You can feel it when you speed up, or slow down, or go around a corner, or hit a bump, or travel on a rough road (where you're bouncing up and down a lot).  But as long as your motion is perfectly smooth, you can't feel it--it feels the same as standing still.

And that's the way it is on the surface of the earth.  The motion is perfectly smooth, so we can't feel it.  We don't feel the wind blowing past us as we circle the earth, because the air is moving along with us at the same speed (just like the air inside your car when you have the windows rolled up).  One of the few ways we can tell that the earth really is rotating is to watch the stars and the sun and the moon go past in the sky.

How the earth _started_ spinning is harder to explain.  It has to do with something called angular momentum.  The earth formed as a result of gravity pulling things together and gas pressure and collisions pushing things apart.  Whenever you have a lot of forces pushing and pulling in all directions for millions of years, you almost always end up with some kind of spinning motion.

The theory for why it doesn't stop is also due to Isaace Newton.  Before Newton's time, people thought that things just slowed down and stopped "by themselves"; but Newton said NO--he said that things slow down because of opposing forces like friction; and if you remove all the opposing forces like friction, the thing could just go on forever.  And that is what happens in the case of the earth.  There really isn't anything to slow it down, so it's been spinning "by itself" for billions of years.

Answer 5

There is a prevailing theory called the Big Bang Theory, which states our universe began with a very very big explosion.  That explosion inserted energy into our universe.  A very very very small portion of that energy ended up spinning our Earth.  As there is very little in space to slow its spin down, it has been spinning ever since Earth began about 4 or 5 billion years ago.

Contrary to the first answer, we are not in perpetual motion.  Although there is very little in space to slow us down, there is something.  For example, our Moon's gravity in part sets up the ocean tides.  These tides create friction on the surface of our planet and that represents energy loss.  As the Earth loses energy, its spin slows down...not very much each year, but it does slow down.  Millions of years from now, if something else doesn't happen to prevent it, the Earth will stop spinning altogether.  Bottom line, there is no such thing as a perpetual motion machine, not even Earth is one.

In fact we do feel the spin, but we grew up with it; so we don't pay attention to it any more.  For example, the direction of the major winds is determined in part by the spin of Earth.  And, to a point, if the Earth stopped spinning, you would see a slight gain in your weight on the bathroom scale.  We don't feel wind generated by our spin around because the atmosphere is spinning with us at about the same rate.

Good question.

Answer 6

Good question.  An axis is just the name of the imaginary line that an object rotates around.  In the case of the Earth, its the line that connects the north and the south pole (going through the center).  The Earth's axis is at a 23.5 degree angle with respect to the perpendicular of the ecliptic plane.  The ecliptic plane is the plane that the earth traces out as it orbits the sun and the perpendicular to that is, well, the line that is perpendicular to it.

So imagine taking a piece of paper and drawing a circle on it.  If that circle is the orbit of the earth around the sun, then the piece of paper is the ecliptic plane.  Now, if you took, say, a toothpick and stood it straight up on that circle, that's the perpendicular to the ecliptic plane.  Then if you tilt that toothpick a little bit (23.5 degrees to be exact), then that's the angle that the earth is spinning at.

Next... The reason we don't feel the earth moving is because we're all moving with the earth too.  Think about when you're in the car and just cruising along.  You don't feel yourself moving.  You only feel something when the car speeds up or slows down.  You feel something when the car accelerates or decelerates because acceleration and deceleration exert a force on things.

The Earth isn't accelerating or decelerating.  Its just going along at a constant speed and we're all along for the ride, so we don't feel it.

I hope that all makes sense and helps.

Answer 7

the earth is spinning on its axis because there is no friction to stop it.

its in perpetual motion. and by newton's first law that a body will continue on its path unless acted upon by an external force.

how it started goes back to the big bang theory that hot gases exploded. pieces were thrown out which formed the stars and the planets.

you don't feel it because its not accelerating, Its constant. If u sit in a car for a while and the car is going at a constant speed then u dont feel the car is moving. u only feel it where there is a change in the speed. this is also explained by newton's laws of motion.