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The force of a sun's gravity can decrease as it's mass decreases as it's hydrogen is converted into energy, and the gravity of a sun large enough can increase if it supernovas and then collapses in on itself to form a black hole, but gravity on earth can't really change unless there is some cataclysm, such as the earth being broken into pieces by a collision with another world or something to change it's mass.

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16y ago
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15y ago

In a sense it does. It has more to do with acceleration, I think. If you were near a very large black hole, for example, you would have to be orbiting rapidly to avoid going below the event horizon. While accelerating and orbiting, time would pass differently for you than for a distant observer. I could be mistaken about this, but just being on planets with large differences in gravity doesn't by itself influence time.

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12y ago

If you are referring to special general relativity then gravity affects time by slowing it down.

The reason behind the idea is to explain why speed of light is always the same no matter the observer momentum.

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14y ago

it slows time read below Imagine a pair of twins, Alice and Bob, who will live to exactly the same age. Rather than giving this age in years, which might be confusing in what follows, let's say each will live for one billion heart beats, and their hearts beat at 60 beats per minute. Alice, a hurricane hunter by trade, has become bored with Earth's puny storms and has moved to Jupiter to chase its Great Red Spot, a centuries old cyclone of truly mammoth proportions. Now gravity is stronger on Jupiter than on the Earth, one consequence being that Alice weighs more. But more interestingly, Albert Einstein's theory of general relativity - his theory of space, time and gravity - says that, due to the lower gravitational potential on Jupiter than on Earth, time as experienced by Alice is moving more slowly relative to time experienced by Bob back on the Earth. What does this mean? First, the word 'relative' is crucial here: it means that as far as Alice is concerned, nothing in her own experience indicates to her that time is moving more slowly. The point is, more slowly relative to what? Alice herself feels nothing out of the ordinary, for instance her heart still beats at 60 beats per minute according to her wristwatch. It is only when Alice and Bob comparetheir experiences of the passage of time that they notice something very strange. For example, when they speak with each other over the satellite link, Bob notices that Alice's voice is a bit deeper and she is speaking more slowly - exactly like a tape recording replayed at a slightly slower speed. But Alice does not feel that she is speaking slowly, or thinking slowly, or anything else for her is happening more slowly. And from Alice's point of view, she notices that Bob's voice is higher pitched than she remembers, and he is talking (and thinking, and doing everything else) a bit faster - exactly like a tape recording played back at a faster speed. More to the point, when Bob puts the microphone next to his heart, Alice hears it beating at faster than 60 beats per minute according to her wristwatch (and her heart); conversely, Bob hears Alice's heart beating more slowly than his. Both agree that Alice could return to Earth before her billion heart beats run out and attend Bob's funeral. How is this possible? Why does gravity affect the rate at which time moves? One of the simplest ways to understand this begins with Einstein's equation E = mc2, which says that mass is a (very concentrated) form of energy. As a consequence of this, Einstein reasoned that it would be possible to build a perpetual motion machine (and thus get something - energy - for nothing) unless gravity slows time. The machine in question is show in the figure. It consists of a vertical conveyor belt stretched between two pulleys which, to keep things simple, we imagine to be frictionless. Attached to the belt are a number of identical, equally spaced buckets, each of which contains a single atom of mass m. Now suppose each of the atoms on the left side of the belt have absorbed a photon of energy ÄE. These excited atoms have more energy, and hence more mass. Using E = mc2, the increase in mass is m = ÄE/c2. With the whole apparatus in the gravitational field of the Earth, the force of gravity will be greater on the excited atoms (each with mass m+Äm) than the ground state atoms (each with mass m), resulting in a net force causing the conveyor belt to tend to rotate counter clockwise. To keep the conveyor belt moving we arrange for the excited atoms to emit a photon of energy ÄE as they reach the bottom, returning them to their ground state (with mass m). We then use a mirror to direct the emitted photons up to the top, and use these photons to re-excite the ground state atoms as they arrive at the top of the conveyor belt. Assuming the energy of the photons received at the top is ÄE (the same energy they had at the bottom), we clearly have a perpetual motion machine: the heavier, excited atoms will always be on the left, the lighter ground state atoms on the right, resulting in a constant, net tendency for the belt to rotate counter clockwise. We could use this tendency to make our machine do useful work. Energy for nothing! All the world's energy problems solved! Of course, this must be impossible. But where is the mistake in our reasoning? A bit of thought reveals that the mistake is in assuming that the energy of the photons received at the top is ÄE. In fact it must be less than ÄE; call it ÄE'. How much less? In being lowered from the top to the bottom (through a height h, say), each excited atom loses a gravitational potential energy of (m+Äm)gh, where g = 9.8 m/s2. However, for each excited atom thus lowered, there is a ground state atom raised, which gains an amount of energy mgh. The net gain in energy is the difference: (m+Äm)gh - mgh = Ämgh. To avoid this net gain (energy for nothing), it must be true that Ämgh is precisely equal to the energy lost by the photon as it travels from the bottom to the top, i.e. ÄE [bottom]- ÄE'[top] = Ämgh. One may imagine the photon losing energy as it climbs against the Earth's gravitational field much like a rock thrown upward loses kinetic energy as it slows down, the main difference being that the photon does not slow down; it always moves at the speed of light. Using Äm = ÄE/c2, the previous equation reads: ÄE - ÄE' = ÄEgh/c2. Dividing both sides by ÄE and rearranging terms we get: ÄE' / ÄE = 1 - gh/c2. Finally, we also know that the energy of a photon is proportional to its frequency (the proportionality constant being Planck's constant). So we can rewrite our equation as: f' / f = 1 - gh/c2, where f is the frequency of the photon at the bottom and f' is the frequency of the photon at the top. Since 1 - gh/c2 is less than one it says that the frequency of the photon received at the top (as measured by a clock at the top) is less than the frequency of the photon that left the bottom (as measured by a clock at the bottom). This is a very strange result. To appreciate why, it will help to switch from the particle picture of light (photons) to the wave picture, and recall that light, which is just electromagnetic waves, can be produced by an oscillating electric charge. Our result says that if Bob is standing on the surface of the Earth holding an electric charge in his hand, and waving his hand back and forth once per second (f = 1), then Alice, standing at the top of a tower of height h, will receive electromagnetic waves of frequency f' < 1. Said more directly, wave crests of light leaving Bob's hand once every second (one second according to his wristwatch), will arrive at Alice's position at a rate of less than once every second (one second according to her wristwatch). See the figure. But wouldn't this require the number of wave crests between Bob and Alice to be continually increasing with time? Can't be! With a fixed distance h between the two, such a continual bunching up of wave crests would require the wavelength of the light (distance between crests) to be getting smaller and smaller as time goes on. Since the speed of light is always the same, smaller wavelength means higher frequency, which means Alice would be seeing light of higher and higher frequency as time goes on. And this is definitely not happening: Alice sees light of constant frequency, f'. (Also notice that f' < f means the wavelength is longer for Alice than it is for Bob; the wave train 'stretches out' as it moves upwards, as shown in the figure.) But if there is no bunching up of wave crests, how is it possible that Alice sees fewer than one wave crest per second according to her wristwatch (i.e., more than one second of Alice-time elapses between crests), unless time itself is moving more quickly at Alice's location than at Bob's? This is the effect of gravity on time! The hands on Alice's wristwatch spin around faster than the hands on Bob's wristwatch. Alice's heart beats faster than Bob's. Here is an alternative way to see this. As Bob is waving his hand back and forth, a wave crest leaves the electric charge in his hand each time it reaches the right end of its back and forth arc (see the figure). Any other light illuminating Bob's hand (that allows Alice to see Bob) will travel to Alice at the same speed as the wave crests of light leaving the electric charge in his hand. This means that when Alice looks down at Bob she must see his hand waving back and forth at the same frequency that the crests of light from the electric charge are reaching her, i.e. at the frequency f' < 1. Thus, Alice sees Bob waving his hand at a rate of less than once per second according to her wristwatch. Bob appears to be waving his hand in slow motion! Indeed, everything about Bob and his surroundings on the ground will appear to Alice to be happening in slow motion. Conversely, Bob will see Alice in fast motion, like a video on fast forward. Notice, also, the longer Alice waits at the top of the tower, the greater the difference that will accumulate between the number of seconds (and heart beats) she experiences and the number Bob experiences. Eventually climbing back down from the tower and comparing notes, both will agree that more seconds (and heart beats) have elapsed for Alice than for Bob. Alice will be older than Bob because she has spent time in a place (height h above the Earth) where time itself moves more quickly relative to time on the Earth's surface! In the case of Alice going to Jupiter, the gravitational potential will at first increase as she leaves the Earth's surface (her time will move more quickly relative to Bob's time, as just discussed), and will continue to increase as she travels away from the Sun towards Jupiter. But eventually the gravitational potential will decrease to a value lower than that on the Earth's surface as she descends into Jupiter's very strong gravitational field. On Jupiter her time will be moving more slowly relative to Bob's time, as described at the beginning of this essay. So how big is the effect of gravity on time? Very tiny, at least as far as we are able to experience here on the Earth. For example, taking h= 100 metres gives f' / f = 1 - gh/c2 0.99999999999999. This means that Bob's clock is running 99.999999999999% as fast as Alice's, meaning we would have to wait a very long time for a noticeable difference in age to accumulate. Nevertheless, the effect has been measured using very accurate atomic clocks and the results are in excellent agreement with our formula. Indeed, the Global Positioning System (GPS), which relies on very accurate atomic clocks both on the Earth and carried by satellites high above the Earth, must account for this effect in order to work with the accuracy it does. It should be emphasized, however, that this warping of time, while small anywhere in our solar system, is huge in other more interesting places in our universe. A black hole is an extreme example, where gravity is so strong at the event horizon that time is slowed to a stop relative to anyone outside the horizon! But this is another story…

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13y ago

As we all know that space(the three dimensions) and time are interlinked and are called space-time(time being the fourth dimension). Gravity of any star or planet warps this space-time fabric, therefore elongating both space and time(take a big bowl, spread a cloth over it tightly and put a ball over it. This will show the warping). So we can say that the more is the gravity the slower the time will pass.

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Q: Can anyone explain how gravity affects time?
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Does gravity affect the speed of light?

Gravity affects the fabric of space-time. So both space and time will be distorted.


Do planes have gravity when in the air?

Yes, gravity affects everything that has mass, everywhere, all the time. In the case of an airplane, gravity is pulling the airplane down. The engines move the airplane forward, and the speed of the air over the wings causes lift, which pulls the aircraft UP. The friction or "drag" of the aircraft moving through the air causes the plane to slow down. It's a delicate balance; the thrust of the engines, and the drag of the airflow, and the airflow causing lift which counteracts gravity. But you can do one simple experiment which proves that gravity affects the plane and everything in it. When you are in an airplane in flight, take your inflight magazine and hold it about 10 inches above your lap; then let go. Gravity affects the magazine and pulls it down.


Why does gravity slow down time?

think of it this way gravity is the time so the more gravity the more time. with out gravity there would be no time because of gravity stuff happens. with out time there would be no gravity. so you can think of it as the same think instead of diffrente thinks.


What variable affects the number of swings in a given amount of time?

GravityMassRotation of the earth, the spinning of the Earth which acts on the path of the swinging object.And lastly friction (very small effect)But the most powerful effect of a swinging object is gravity


How can a gravity pull an object?

Every time you jump, you experience gravity. It pulls you back down to the ground. Without gravity, you'd float off into the atmosphere -- along with all of the other matter on Earth. You see gravity at work any time you drop a book, step on a scale or toss a ball up into the air. It's such a constant presence in our lives, we seldom marvel at the mystery of it -- but even with several well-received theories out there attempting to explain why a book falls to the ground (and at the same rate as a pebble or a couch, at that), they're still just theories. The mystery of gravity's pull is pretty much intact.

Related questions

Does gravity affect the speed of light?

Gravity affects the fabric of space-time. So both space and time will be distorted.


Why is the world one 1 hours slow?

Because gravity affects time. I saw a documentary about it.


When you tip a syrup bottle upside down, it takes a long time for all the syrup to move down Explain this?

Gravity is taking its time?


How does the laws of gravity explains the relationship between mass and garvity?

Newton's law of gravitation doesn't really "explain" the relationship, it just states it. On the other hand, the General Theory of Relativity explains that masses distort space-time; this, in turn, affects the movement of other masses.


Explain why the relationship between orbital speed and distance is the same as that between gravity and distance?

gravity is that keeping the orbital speed from falling or breaking loose. and the distance away = time


What is Time line of the history of soccer?

The timeline of soccer is way to big for anyone to explain. Sorry.


If a planet has less gravity will it take longer to revolve around the sun?

No, it is the sun's gravity that affects the planets revolutions. The planet's distance from the sun is also very important in the time it takes to revolve around the sun.


Which principle was unknown in the time of Copernicus but later made it possible to explain a mechanism by which the earth orbits the sun?

The gravity of the sun attracts the earth.


Do planes have gravity when in the air?

Yes, gravity affects everything that has mass, everywhere, all the time. In the case of an airplane, gravity is pulling the airplane down. The engines move the airplane forward, and the speed of the air over the wings causes lift, which pulls the aircraft UP. The friction or "drag" of the aircraft moving through the air causes the plane to slow down. It's a delicate balance; the thrust of the engines, and the drag of the airflow, and the airflow causing lift which counteracts gravity. But you can do one simple experiment which proves that gravity affects the plane and everything in it. When you are in an airplane in flight, take your inflight magazine and hold it about 10 inches above your lap; then let go. Gravity affects the magazine and pulls it down.


Why does gravity slow down time?

think of it this way gravity is the time so the more gravity the more time. with out gravity there would be no time because of gravity stuff happens. with out time there would be no gravity. so you can think of it as the same think instead of diffrente thinks.


What causes black holes to form?

When a star collapses all the gravity that it created also collapses creating a wrinkle, fold, hole (hard to explain) in the fabric of space time.


How does the traditional theory of the formation of the galaxy explain the origin of globular clusters?

Cluster's form because gravity gradually builds a center of mass which over time accumulates more and more matter which can explain the formation of galaxies as well as globular clusters.