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

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Discussion Overview

The discussion revolves around the relationship between the Earth's rotation and revolution, specifically whether they occur at the same speed and in the same direction. Participants explore concepts of linear and angular velocity in the context of the Earth's motion.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested, Mathematical reasoning

Main Points Raised

  • Some participants clarify that "rotation" refers to the Earth's spin on its axis, while "revolution" refers to its orbit around the Sun.
  • One participant argues that the Earth does not rotate and revolve at the same speed, noting that rotational speed varies by location, being highest at the equator.
  • Another participant provides numerical values for the Earth's rotational speed at the equator and its orbital speed around the Sun, suggesting a significant difference between the two.
  • There is a focus on angular velocity, with some participants asserting that it should be considered when discussing the Earth's motion.
  • Questions arise about the calculation of angular velocity and its relationship to linear velocity, with references to formulas involving radius and angular velocity.
  • Participants engage in a back-and-forth regarding the interpretation of angular velocity and its implications for understanding the Earth's motion.

Areas of Agreement / Disagreement

Participants express differing views on the relevance of linear versus angular velocity in understanding the Earth's motion. There is no consensus on whether the rotation and revolution speeds can be directly compared or how to properly calculate them.

Contextual Notes

Some participants mention the need for specific calculations and the importance of considering angular distance and time in these calculations. There are unresolved questions about the definitions and implications of angular versus linear velocity.

monty37
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does the Earth rotate and undergo revolution with the same speed?is the rotation
and revolution in same direction
 
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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
 


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.
 


but it is the angular velocity that has to be taken,as Earth undergoes rotatory motion.
 


monty37 said:
but it is the angular velocity that has to be taken,as Earth undergoes rotatory motion.
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.
 


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?
 


monty37 said:
if angular velocity had been taken into account,then the velocity should
have been in radians/sec.

The figures in my post are given as angular velocity, albeit somehwat indirectly.
 


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?
 


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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