View Full Version : Speed of the earth's rotation
maxwellhunt
Mar 1, 2007, 05:38 PM
At what speed does the earth revolve around the sun
saturday
Mar 1, 2007, 05:44 PM
30 kilometers per second
TechSupport
May 3, 2007, 11:23 AM
More info about the earth's rotational speed at Speed of the Earth's Rotation (http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970401c.html)
Stratmando
May 22, 2007, 05:34 PM
1 RPY(Revolution per year(Earth)). At the bottom end of the dial. It spins about 365 times during that time
Starman
May 23, 2007, 07:43 PM
Approximately 65,000 mph or (105,000 kph), which is approx. 18 1/2 miles a second.
One thing to remember is that Earth's orbit is slightly elliptical which causes it to accelerate as it gets closer to the Sun and decelerate gradually as it moves away giving it an average speed of 29.658 km/s. In short, its fastest when closest to the Sun--perihelion--and slowest when farthest from the Sun--aphelion.
Speed of the Earth in Orbit (http://hypertextbook.com/facts/2000/IlanaEpstein.shtml)
Capuchin
May 23, 2007, 10:29 PM
Errrm, starman did you just use commas in 2 different ways here?
Starman
May 24, 2007, 03:47 AM
Errrm, starman did you just use commas in 2 different ways here?
Average speed of 29.658 km/s
Thanks for pointing out the typo.
lew lew 12345
Jun 25, 2007, 07:00 AM
at what speed does the earth revolve around the sun
6000mph
Skrypt
Jul 15, 2007, 07:13 PM
HOLY CRAP. That means if somehow by freak force of nature that the earth slowed down everything would fly around.
TechSupport
Jul 16, 2007, 06:46 AM
HOLY CRAP. that means if somehow by freak force of nature that the earth slowed down everything would fly around.
This is not true. The Earth, unlike any spinning object you can possibly hold and touch, has an immense gravitational field. It is not centripetal force that holds you to the surface of the earth, it is gravity.
The Earth's gravity is is pulling you towards it at the rate of 9.8 meters per second per second. If it slowed down to no spin whatsoever, there would still be gravity. It is dependent solely on the mass of two objects (you and the earth) and the distance between them. The closer the distance, and/or the larger the mass, the greater the gravitational force between the two.
Check out Earth's Mass - EnchantedLearning.com (http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Mass.shtml) for more information about figuring out gravity equations.
Capuchin
Jul 16, 2007, 08:53 AM
This is not true. The Earth, unlike any spinning object you can possibly hold and touch, has an immense gravitational field. It is not centripetal force that holds you to the surface of the earth, it is gravity.
The Earth's gravity is is pulling you towards it at the rate of 9.8 meters per second per second. If it slowed down to no spin whatsoever, there would still be gravity. It is dependent solely on the mass of two objects (you and the earth) and the distance between them. The closer the distance, and/or the larger the mass, the greater the gravitational force between the two.
Check out Earth's Mass - EnchantedLearning.com (http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Mass.shtml) for more information about figuring out gravity equations.
Actually, the Earth would have to spin FASTER to through you off, not the other way around as skrypt says. Centripetal force is required to make something move in a circle, gravity provides this force. Gravity is constant, so if the Earth spins so fast that you need 9.8m/s/s of centripetal acceleration, there's no gravity left to attract you towards the Earth, you'd be effectively in orbit at ground level.
Starman
Jul 26, 2007, 09:34 PM
Orbit is impossible without gravity.
Orbit - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Orbits)
Centripetal force - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Centripetal_acceleration)
Capuchin
Jul 26, 2007, 10:12 PM
I didn't say there was no gravity...
TechSupport
Jul 27, 2007, 05:42 AM
Okay, I think the question has been answered. The rest of this conversation is answering a much different question (or set of questions).
Capuchin
Jul 27, 2007, 05:46 AM
But equally intriguing :)
TechSupport
Jul 27, 2007, 06:14 AM
Astromechanics is my favorite topic. I'd love to take over the world and discuss nothing more than gravitational tides and retrograde motion due to inertial displacement from angular momentum, but I have to earn a living. :)
Starman
Jul 27, 2007, 02:47 PM
I didn't say there was no gravity....
What did you mean by no gravity and being in orbit then?
quote
So if the Earth spins so fast that you need 9.8m/s/s of centripetal acceleration, there's no gravity left to attract you towards the Earth, you'd be effectively in orbit at ground level.
Capuchin
Jul 27, 2007, 03:49 PM
I meant that gravity would be providing the centripetal acceleration needed for circular motion i.e. orbit. You would be in freefall at ground level.
I see that what I did say was ambiguous, I apologise.