# shouldn't gravity travel at light speed immediately

if gravity travels at c(light speed), why aren't objects pulled to earth at that speed?

Since the velocity of gravity is 9.8 meters per second squared, will it eventually accelerate until it maxes out at c then hold constant?

And if that is the case, then why doesn't the gravitational pull between objects and earth immediately travel at c like photons?

so the acceleration of gravity is 9.8 meters per second squared only on earth.

The gravitational pull is contingent on the body off mass and the distance between the masses.

Gravity waves travel at the speed of light.

So if a gravity wave extending from one primary object of greater mass to another object of lesser mass was to move a lights speed it wouldn't affect the speed or acceleration of the secondary object. the secondary object would just react to the primary object at the speed of light, but the reaction it self is dependent upon the size and distance between them?

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More on speed of Gravity: physics.stackexchange.com/q/7041/2451 –  Qmechanic Apr 19 '12 at 23:13
Where you got that the velocity of gravity is 9.8 meters per second squared? Notice that velocity is measured in meters per second, not in meters per second squared. –  Anixx Apr 20 '12 at 1:12

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9.8 m/sec/sec is not the speed of gravity, it is the acceleration due to gravity at the surface of the earth. At the surface of the moon it is a good deal less. At the surface of the sun it is a lot more.

It is true that if you could fall in a straight line, gaining 9.8 m/sec every second, after about a year you would approach the speed of light, but you would never surpass it. It would be hard to find such a building to jump out of. You could do it in space if you had a good enough rocket motor and enough fuel.

Think about sound in air. The speed of sound is about 340 meters/second, but that does not mean if the wind blows something around, it blows it at that speed. What it means is if someone claps their hands 340 meters away, you hear it one second later.

Gravity is like that. If a big piece of matter, like a planet, suddenly moves into position 30 000 kilometers away, its gravity is felt by you 1/10 second later. But that only means you feel the force at that time, not that you are traveling at that speed.

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Also, this 9.8 $m/s^2$ is only true near the earths surface, so there is not enough time/distance to accelerate to $c$ anyhow. –  Bernhard Apr 20 '12 at 5:35