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Does the earth rotate and undergo revolution with the same speed?

  1. Sep 9, 2009 #1
    does the earth rotate and undergo revolution with the same speed?is the rotation
    and revolution in same direction
     
  2. jcsd
  3. Sep 9, 2009 #2
    Re: speed

    From your question, I will understand "rotate" as the Earth spinning on an axes, and "revolution" as the Earth going around the Sun.

    In this way, no the Earth does rotate at the same speed as it turns around the Sun. Firstly, because the rotation speed is not the same everywhere on our planet. You will travel at a much higher speed if you are next to the equator, and you will be pratically standing (spinning on yourself) at the poles. Seconldy, even taking the highest rotation spped of our planet (around the equator), you would travel at [tex]1670\frac{km}{h}[/tex] compared to the center. This means that if our planet would stop rotating, the people at the equator would hit the east wall at [tex]1670\frac{km}{h}[/tex].

    On the other hand, the Earth is going around the Sun at [tex]1.076 \times 10^{5} \frac{km}{h}[/tex].

    Cheers
     
  4. Sep 9, 2009 #3

    negitron

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    Re: speed

    You know the Earth's diameter is about 7400 miles and rotates once in 24 hours. You also know the Earth's orbit averages about 93,000,000 miles and completes once every 365 days.

    Do the math and you tell me.
     
  5. Sep 11, 2009 #4
    Re: speed

    but it is the angular velocity that has to be taken,as earth undergoes rotatory motion.
     
  6. Sep 11, 2009 #5

    Hootenanny

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    Re: speed

    Yes, what it your point?

    fatra2 takes into account the angular velocity of earth and negitron gives you all the information you need to compute it.
     
  7. Sep 11, 2009 #6
    Re: speed

    if angular velocity had been taken into account,then the velocity should
    have been in radians/sec.

    so the angular distance required to calculate this would be the elliptical path
    divided by time(365x 24x3600)?right

    so this would this be the velocity of earth to aperson in space?
     
  8. Sep 11, 2009 #7

    negitron

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    Re: speed

    The figures in my post are given as angular velocity, albeit somehwat indirectly.
     
  9. Sep 11, 2009 #8
    Re: speed

    may i know in what indirect way,is it in terms of v=rw,i mean has the radius been
    multiplied with ang velocity and given as linear velocity?
     
  10. Sep 11, 2009 #9

    negitron

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    Re: speed

    What does it mean when I tell you, for example, that the Earth has a diameter of 7400 miles and it makes one revolution in 24 hours? Can't you relate that to an angular velocity with simple arithmetic?
     
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