• Question: What speed does the earth rotate at

    Asked by emmacos123 to Aggelos, Andrew, Eileen, Naomi, Shane on 20 Nov 2012.
    • Photo: Shane Bergin

      Shane Bergin answered on 20 Nov 2012:

      You can work this out! Here’s how i’d do it

      We’re working out a speed – so that’s distance over time

      the earth takes 1 day to revolve on its axis (that’s the time take).

      so what’s the distance? oo.. we come to a tough bit… the earth is fatter at the equator than it is up here at 51degrees (where ireland is). so, lets assume you’re on the equator. the distance around the equator is 40,000km

      So speed = distance/time = 40,000km/24hours = 1666km/hr! That compares with the cruising speed of a Jumbo-jet of 900km/hr

    • Photo: Eileen Diskin

      Eileen Diskin answered on 20 Nov 2012:

      Well, the Earth as a whole takes one day to make a complete rotation. But how fast its rotating depends on where you are. It moves a lot faster at the equator, because that’s where the Earth is its fattest. At the North and South poles, it rotates a lot slower – theres just less distance that it has to cover in one day.

      So at the Equator, where its moving fast, you might wonder…whoa! how come peopel don’t feel it? or fly off? Well, because of gravity, which keeps us on Earth. And because of this, and the Earth is moving at the same speed as us, we don’t really notice it (sort of like when you’re in a car or an airplane, it doesn’t always feel like you’re going so fast).

      Where you are on Earth – like the equator or at one of the poles – also has an effect on how much sunlight you get. My brother lives in Alaska, which is really far towards the north pole. And in the winters, he doesn’t get any sunshine at all for a few weeks! I don’t think I’d be able to deal with that…and in the summers, it never gets dark for a few weeks.

    • Photo: Andrew Jackson

      Andrew Jackson answered on 21 Nov 2012:

      i like these maths puzzles such as shane worked out.

      I just want to add that the earths rotation has a strong effect on the pattern of winds around the earth. Essentially the rotation puts a twist on the winds that would otherwise travel in north-south or south-north directions. This is what makes our prevailing winds in ireland blow an angled south-west direction. Its called the Coriolis Effect if you want to read more http://en.wikipedia.org/wiki/Coriolis_effect and was one of my favourite parts of Geography when i took some classes in it in University during my general science degree (although in the end i choose to specialise in zoology)

    • Photo: Aggelos Zacharopoulos

      Aggelos Zacharopoulos answered on 22 Nov 2012:

      @ emmacos123,
      the guys above have looked at the speed that the earth is rotating around itself (its axis). I looked at how fast earth rotates around the sun.

      The distance of the earth from the sun is on average 150 million km so a total 360 degree rotation would be 2 x 3.141592 x 150 million Km = 943 million Km long!!!

      and as we know a full rotation of the earth around the sun takes on average 365 days or 365×24= 8,760 hours

      So the erath travels 943 million Km in 8,760 hours which gives an average speed of 943 millions/8,760 = 107,648 km/h !!!!

      and we can’t feel a thing 😉