The earth takes exactly 24 hours for one full rotation calculate

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Homework Help Overview

The discussion revolves around calculating the speed of rotation of a point on the Earth's equator, specifically in the context of A2 physics and uniform circular motion. Participants are attempting to derive the speed based on the information that the Earth takes 24 hours for a full rotation.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants are using the formula for speed in circular motion, questioning the radius of the Earth and its impact on the calculation. Some are exploring rounding differences in their calculations, while others are discussing the implications of the Earth's rotation relative to the Sun and stars.

Discussion Status

There are multiple calculations being shared, with some participants providing specific values for the radius of the Earth and discussing the resulting speeds. Guidance has been offered regarding the use of parentheses in calculations and the importance of using the correct radius.

Contextual Notes

Participants note that the only information provided is the 24-hour rotation period, leading to questions about the radius and the assumptions made in the calculations. There is an acknowledgment of the complexity introduced by the Earth's orbit around the Sun.

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the speed of rotation of a point on the equator

the title is the only information I have been given to work out this questions and it relates to a2 phyics uniform circular motion and the answer is 465ms-1 I just cannot get it I know the eqautor must have something to do with it PLEASE HELP

Full calculations shown please!

the textbook gives equations speed = 2pi*r/T but I am not given radius and using the radius does not give the correct answer anyway

the closest I got was 471 ms-1 using pi/24*3600 and I just used pi because I am assuming because it asks along the equ I should use 180 degrees
 
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If you're getting 471, it could just be a matter of how you're rounding some of the variables like pi or the radius of the Earth.

I used the exact same equation using the pi option on my calculator and for r, I used 6.378x10^6 and I got 463.82m/s.

Hope this helps!
 
The Earth takes 24 hours to make a full rotation with respect to the Sun. The Earth is also orbiting the Sun. This means it takes a bit less than 24 hours for that Earth to make a full rotation with respect to the stars. Another way to look at it is that the Earth rotates a bit more than 360 degrees in 24 hours. This extra little bit of rotation is what gives that answer of 465.1 m/s as opposed to the 463.8 m/s that gbaby370 obtained.
 
sazzy said:
the speed of rotation of a point on the equator

the title is the only information I have been given to work out this questions and it relates to a2 physics uniform circular motion and the answer is 465ms-1 I just cannot get it I know the equator must have something to do with it PLEASE HELP

Full calculations shown please!

the textbook gives equations speed = 2pi*r/T but I am not given radius and using the radius does not give the correct answer anyway

the closest I got was 471 ms-1 using pi/24*3600 and I just used pi because I am assuming because it asks along the equ I should use 180 degrees

Hello sazzy. Welcome to PF.

Look up the radius of Earth.

Using that, you can find circumference of Earth, which is the distance that a point on the equator travels in one day.

The number of seconds in one day is 24*3600.

If you want to divide some number by 24*3600, you should put (24*3600) in parentheses.

When you computed π/24*3600, that was equivalent to 3600*π/24 . It's just a coincidence that this gave a result that's close to the correct answer.
 

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