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If the earth spin the opposite direction wouldn't that change gravity and the way things will go? If the spinning of the earth go to the east, and if we would change the way it could put the gravity out.
Question Date: 2017-10-30
Answer 1:

Gravity is a universal force that acts on all objects -- it essentially tries to bring objects closer together, and it works on objects regardless of their spin/movement.

The reason that we stay "attached" to the Earth's surface is that the earth is massive, so it exerts significant gravitational force on us. Although the Earth's spin does affect gravity slightly, if the earth were to stop spinning (or spin the other direction) gravity would still keep everything in its place. One interesting related fact about gravity is that the acceleration due to gravity is actually slightly smaller in magnitude at the equator than at the poles because of centrifugal force caused by the Earth's spin, so you would weigh less at the equator than you do here!


Answer 2:

Actually, the direction that the earth spins doesn't really affect the earth's gravity. Gravity is something that depends on the mass and size of something. So anything that has mass has gravity. That means that even YOU have your own little gravitational field, but it's not a very big gravitational field because you don't have that much mass. The Earth's gravity is a force that pulls you towards the earth.

Things that are spinning really quickly, like the earth, actually create a force that moves in the opposite direction of gravity. So because the earth is spinning, it's actually creating a second force, called "centrifugal force" that pushes you away from the earth a little bit. To understand this, try a little experiment: take a yo-yo or tie something like a pencil to the end of a string. Hold the other end of the string and start spinning in a circle really quickly. What happens to the pencil or the yo-yo? It moves away from you! This is what's happening on Earth. It actually causes our planet to bulge a little bit around the equator: instead of being a perfect sphere, we're a little more football shaped.

Luckily the earth's gravity is much bigger than centrifugal force so we don't go flying off of our planet. If the earth were spinning the other way, all of the forces would balance out like they do now so the gravity that we feel wouldn't change at all.


Answer 3:

Hey, super cool question!

Lets start interesting background about your question. The reason the earth spins the way it does is because it was basically "born" that way. When our sun (which is in the Milky Way) formed, it began pulling dust floating around in space towards it. This is due to the gravity of the sun. This dust started to move in a circle around the sun, and over millions and millions and millions of years, this dust began clumping together, and eventually formed Earth (as well as all the other planets in the Milky Way like Venus and Mars and all the others). So the spinning of our earth was basically decided based on how dust first started circling our sun.

Most planets in the Milky Way spin in the same direction as Earth, but some planets do not... why is that? Well, its because something HUGE smashed into them with so much power that it actually made them start spinning the other way. Think about that. That's amazing! So how would the earth start spinning the other direction? It would only be possible if something really big smashed into it (like a really big meteor or asteroid).

But what exactly would happen if the earth started spinning the other way...Well, it would be pretty bad. But the main effect would be that all the weather on Earth would change. You should look at this cool website, it shows all the wind patterns and storms on earth happening right now.

Earth

All weather patterns on Earth are caused by the spin of the earth. If the spin changed, so would the weather. For example, all storms in the top half of the earth spin one way, and those on the bottom half spin the other way because of which direction the earth is spinning. So even by changing spins of storms, you change where they will go and how they will behave - changing a lot. Hurricanes just like the ones that hit the United States and Mexico will go different places, and might even be more powerful!

But what would be worse than the earth spinning the other direction....? If Earth stopped spinning all together!!

See if you can figure out what might happen! Hint: it has to do with the big magnetic field caused by the earth spinning.


Answer 4:

Gravity keeps us from hopping from our porches into outer space. Even though we can't jump into space, the Earth's spinning makes space travel easier. In fact, the U.S. launches rockets from Cape Canaveral in Florida because the rotation of Earth can give a starting boost for rockets–kind of like a slingshot.

How could we make the earth slingshot stronger? We would need to make the earth spin more than 20 times faster to jump off the face of the earth.

You can think about the earth like a top. Places near the top and bottom aren't moving as quickly as those which whip around the center. Although polar bears and penguins spin slowly they don't fly off to the Moon or Mars. That's because gravity makes them stay here!


Answer 5:

The spin of the earth has nothing to do with gravity. The earth has gravity because it has mass, and changing the spin would not change the mass.


Answer 6:

Great question! The gravity between two objects (such as you and the earth) depends only on their mass (weight, effectively) and the distance between them. Gravity would pull on you just the same if the earth wasn't spinning or spun in the opposite direction. Why? Fundamentally, we don't fully know.

However, the force you feel on the surface of Earth isn't only gravity and other parts of it would be affected by the reversal of Earth's rotation.

For instance, there's the relatively weak "centrifugal force" that pushes you outward when moving in a circle, which you can feel in many amusement park rides or even a tire swing. This depends on how fast Earth rotates, though not which way. However, if Earth were to rotate around a different axis--right now, the North pole is on top, but imagine your school was--this centrifugal force would point away from this new axis instead. What I mean by axis is easily visualized by looking at a spinnable globe--the stick it spins around is its rotational axis!

What is changed by the direction of Earth's rotation is the "Coriolis force," which would flip directions if Earth spun in the opposite way. While this force is also much smaller than gravity (it's generally unnoticeable) and only affects moving objects (like a thrown baseball), it would have a few noticeable effects such as changing the direction of how hurricanes spin! Right now, hurricanes spin counterclockwise north of the Equator (and revere south of it), but these depend on the Coriolis force and would switch!

Another interesting effect of reversing the earth's rotation is that its protective magnetic field(due to molten metals moving in the core) would be likely flipped upside down. This means compasses would point south!



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