1
vote
0answers
23 views

Do we feel the full force of the earths gravity even though the earth is spinning [duplicate]

As far as I know, since the earth is spinning, centrifugal force should be throwing you off the earth. However, gravity counteracts that by being a stronger force. So if you stood an object with the ...
1
vote
1answer
44 views

Do objects in free-fall contribute to earth's weight as a whole still?

If everything in earth's atmosphere contributes to earth's overall weight, including air etc. Does an objects weight in free-fall effect this overall weight in anyway. Just say the weight of earth ...
0
votes
1answer
50 views

Does gravity act in the centre of the Earth? [duplicate]

If we we dig a hole from north pole to the south pole of the Earth and we throw a ball in this hole where would it stop? Will it come back on the surface or it will stop at the centre?
0
votes
1answer
45 views

What would happen if I was in the centre of the Earth? [duplicate]

If right in the centre of the Earth would be like a hole and I could teleport right there, what would happen to me? Would I explode, implode? My own theory is that maybe I would levitate because since ...
2
votes
1answer
49 views

Could the Earth be ejected when the sun burns out?

My younger brother came home from school today and told us at the dinner table that when the sun burns out the Earth could be ejected from its orbit. Skeptical, I asked his source. He quoted his ...
5
votes
3answers
480 views

Does the conversion of crude oil to greenhouse gases have any measurable effect on earth's gravitational pull?

Oil underground is much denser than greenhouse gas in the atmosphere. Does the conversion in anyway effect the gravitational force from earth.
1
vote
0answers
65 views

Could water physically makeup the core of a planet or otherwise large celestial mass?

Knowing very little about the nature of water, wondering how it might behave at the centre of a planet or centre of an another massive gravitational body. Could water take such pressures or might it ...
0
votes
1answer
95 views

What's the reason behind Earth's gravity? [closed]

How can Earth attract any object irrespective of what it is made?
1
vote
2answers
102 views

What happens to gravity in the middle of the earth? [duplicate]

So I was curious about, what if we make a tunnel from one side of the earth, to the other side of the earth? Gravity is ofcourse always negative, which makes you "fall" and not "float". If we take ...
2
votes
4answers
82 views

about the rotation of the earth and gravity, when all continents were merged

A long time ago, I read that the gravity force isn't the same if you are near the Andes Mountains or if you are at Paris. So today I asked to myself if when all continents were one, if the difference ...
6
votes
4answers
1k views

If you could ride an elevator through the earth [duplicate]

What if it was possible to ride an elevator straight through earth. If we take all the heat and pressure problems away, and assume it would be possible: What would happen with gravity? Would gravity ...
1
vote
3answers
75 views

What is the constant $g_0$ used for calculating the specific impulse in seconds?

Wikipedia defines specific impulse as: $$ I_\mathrm{sp} = \frac{F_\mathrm{thrust}}{\dot{m} \cdot g_0} $$ The $g_0$ is said to be the acceleration at the Earth's surface. So is it actually the ...
0
votes
1answer
168 views

Can gravity be reversed?

I'm wondering if any set of hypothetical conditions could result in us gravitating in a different direction. Specifically a reversal of gravity on the surface of Earth (or at least part of it), so ...
110
votes
15answers
32k views

How do I explain to a 6 year old why people on the other side of the Earth don't fall off? [closed]

Today a friend's 6 year old sister asked me the question "why don't people on the other side of the earth fall off?". I tried to explain that the Earth is a huge sphere and there's a special force ...
1
vote
3answers
362 views

how apparent weight varies due to the rotational motion of earth

I learned that as the earth rotates about its axis, the bodies on the earth also follow a circular path. In most books I read, they give the example of a person standing on a weight balance at the ...
0
votes
0answers
216 views

Gravity change as a function of time only

Is it possible to find how gravity changes with time? That is, height is not part of the equation. For example, $g$ can be expressed as a function of height that does not involve time with this ...
0
votes
3answers
825 views

No uncertainty for standard gravitational acceleration?

The other day I asked about the uncertainty of light, and this issue triggered me to start looking into other physical constants and try to understand why other constants have no uncertainty. One of ...
0
votes
1answer
100 views

How faster is the effect of force exerted by gravity? [duplicate]

We all know that Earth revolves around the Sun due to Gravitational force of the Sun. Also we know that it takes just over 8 minutes for the Sun's light to reach Earth. Now let us say, hypothetically ...
1
vote
1answer
129 views

Why does earth spins? [duplicate]

I understand the governing force causing the earth's cycle around the sun is gravity. It can be described by Keplar's law. But what causes the earth's spin? what is its governing law?
0
votes
1answer
290 views

How do “gravity hills” work?

There are many "gravity hills" throughout the world http://en.wikipedia.org/wiki/Gravity_hill I just visited one here yesterday in Burkittsville, Maryland: http://www.roadsideamerica.com/tip/600 ...
0
votes
0answers
924 views

Does gravity change the closer you are to the Earth's core? [duplicate]

Very simple question that has bugged me for some time, does the acceleration produced by gravitation (e.g. $9.8\: \mathrm{m/s^2}$) would change if we placed an observer closer to the planet's core? I ...
2
votes
3answers
166 views

Could we use the coriolis effect to travel

Given a platform that is floating independent of Earth's gravity, would it be possible to put a platform over the equator and over the day, would the Earth rotate from under it allowing you to travel ...
4
votes
1answer
306 views

How would gravity change on a planet rotating around itself very fast?

Let's take a planet identical to Earth, but with rotation speed multiplied by ten thousand. What would happen with the gravity if it was spinning madly around itself? Would the centrifugal force make ...
1
vote
3answers
719 views

Speed of the Moon

Why the motion of the Moon looks very slow in the sky? Doesn't it need the high speed in order to escape the earth's gravity?
2
votes
2answers
1k views

How does earth carry moon with it, if it can not force moon to touch it by gravitational force?

earth's gravitational force is acting on its moon in such a way that it forces moon to rotate round its orbit by centripetal force and carries it while rotating round the sun by gravitational force. I ...
3
votes
2answers
154 views

Does the Earth have a semi-solid body at its core because of lower pressure at the center of the Earth?

I have read that the Earth has a semi-solid iron body at its core, even though that object is surrounded by liquid magma.... I'm wondering if this is because of a pressure (and resulting temperature) ...
5
votes
1answer
512 views

If the Moon had gravity as good as the Earth and a magnetic field could it have supported life?

If the Moon had gravity as good as Earth and a magnetic field could it have supported life? Because if the Moon had gravity, it could have retained water more than is present today on the surface. ...
3
votes
2answers
371 views

Deviation from Earth's orbit

How much orbital deviation is required for the Earth to get knocked out from current orbit so it either moves away from Sun or towards the Sun?
0
votes
1answer
197 views

What is the gravity at the center of the Earth? [duplicate]

Possible Duplicate: Would you be weightless at the center of the Earth? Supposing there is a cavity at the center of the Earth, what is the gravity there? What will be its direction and ...
1
vote
3answers
3k views

If the earth would stop spinning, what would happen?

What would happen if the earth would stop spinning? How much heavier would we be? I mean absolutely stop spinning. How much does the centrifugal force affect us? If you give technical answers (please ...
2
votes
3answers
1k views

Could we make a trebuchet that could launch objects to a stable orbit?

Inspired by this xkcd, which calculated the energy requirements for accelerating individual humans to escape velocity (regardless of consideration for what that would do to your organs), I am ...
-3
votes
1answer
430 views

Gravity anomaly in Lacnov, Slovakia: Gravity ashamed

http://www.youtube.com/watch?v=4qxwqNqL-Nc http://tvnoviny.sk/sekcia/spravy/technologie/v-lacnove-sa-predmety-kotulaju-do-kopca.html (Sorry: above links in Slovak.) Can someone explain this to me? ...
23
votes
4answers
5k views

Would you be weightless at the center of the Earth?

If you could travel to the center of the Earth (or any planet), would you be weightless there?