If earth rotation be able more fast...the gravity will be minor?And vice versa?
2007-03-03 09:24:14 · 6 answers · asked by drfravio 2 in Science & Mathematics ➔ Physics
Gravity doesn't have much of anything to do with rotation.
Law of Universal Gravitation: Each particle of matter attracts every other particle with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
"The standard formula for gravity is:
Gravitational force = (G * m1 * m2) / (d2)
where G is the gravitational constant, m1 and m2 are the masses of the two objects for which you are calculating the force, and d is the distance between the centers of gravity of the two masses."
2007-03-03 09:30:25 · answer #1 · answered by Crissy R 2 · 0⤊ 0⤋
Imagine you are on the surface of the earth at a point on the equator. You are moving around in a big circle, with a radius of 6.3x10^6 m every 24 hours. You are accelerating toward the center of the earth. (Look up centripetal acceleration, if this does not sound correct to you.) So you have a centripetal acceleration equal to 4pi^2 (Radius of the Earth)/(length of a day)^2 = Ac
Now use Newton's second law to consider the forces acting on you while you stand at a point on the equator:
Call forward toward the center of the earth,
mg - Fn = mAc
where m is your mass, Fn = is the upward normal force exerted on you by the ground (the Normal force), and Ac is your centripetal acceleration.
Fn is your apparent weight. If you were to drop something while standing at the equator, it would fall with an acceleration equal to Aapparent, that would be related to this normal force as follows:
Fn = m Aapparent.
Now, if you plug in Aapparent into Newton's second law, way above, and then plug in the expression with the length of the day for Ac, you will see how the apparent acceleration of gravity is related to the earth's rotation. (The people who said the two are not related, did not understand your question.)
2007-03-03 09:47:34 · answer #2 · answered by Dennis H 4 · 0⤊ 0⤋
If the gravity of the earth could change it would fall out of orbit, but the speed of the rotation wouldn't change, because that's dependent on inertia.
2007-03-03 09:32:00 · answer #3 · answered by theacademyisjacksparrow 1 · 0⤊ 0⤋
gravity has to do with the mass of the earth not the rotation
2007-03-03 09:27:15 · answer #4 · answered by Catman 4 · 0⤊ 0⤋
The force due to gravity between (any) two bodies is given by:
F = -GMm/r²
WHERE in this equation do you see anything about rotation?
2007-03-03 09:28:05 · answer #5 · answered by Anonymous · 0⤊ 0⤋
Dennis H is absolutely right. Does something you are spinning around yourself on a string feel heavier or lighter as the speed increases?
2007-03-03 10:01:29 · answer #6 · answered by smartprimate 3 · 0⤊ 0⤋