- #1
Xuvaze
- 12
- 0
Hello! Finals are coming up in less than a week and I received some sample problems as review for the exam. I have my work layed out and a draft for it, but I would like some reassurance, if that's okay. :-)
Anyway, here is the sample problem:
You have been contacted by StM.org (Stop the Myth) to aid them in an upcoming campaign. They are asking you to create a presentation to compare the weight of a person standing on the equator to the centripetal force experienced by that person due to the Earth's rotation. The results of your work will be used to support their effort to dispel the myth that, "People on the equator feel a lot lighter due to the rotation of the Earth."
- You may use any mass for a person in your calculations.
- You must clearly show how you calculated the magnitudes of both forces and how they compare to each other.
- You need to explain whether your answers depend on the mass of the person or would the anyone feel the same way.
- You should clearly state whether the centripetal force makes a significant impact on the weight.
Your answer may be written in any format which best suites your preference. Good luck!
Here is what I got:
The centripetal acceleration at the equator = 4*pi^2*r/T^2
Where T = time period. For Earth, this is 24hours = 86400 seconds.
R = radius of Earth. This is 6400 km = 6400000 meters
Therefore, 4*pi^2*6400000/86400^2 = 0.03 m/s^2
Since the acceleration due to gravity is approx. 9.81m/s^2, then you would weigh only about 0.3% less at the equator than at either the North or South poles.
Is that right? I feel like I am missing something. Any help would be much appreciated! Thanks so much!
Anyway, here is the sample problem:
You have been contacted by StM.org (Stop the Myth) to aid them in an upcoming campaign. They are asking you to create a presentation to compare the weight of a person standing on the equator to the centripetal force experienced by that person due to the Earth's rotation. The results of your work will be used to support their effort to dispel the myth that, "People on the equator feel a lot lighter due to the rotation of the Earth."
- You may use any mass for a person in your calculations.
- You must clearly show how you calculated the magnitudes of both forces and how they compare to each other.
- You need to explain whether your answers depend on the mass of the person or would the anyone feel the same way.
- You should clearly state whether the centripetal force makes a significant impact on the weight.
Your answer may be written in any format which best suites your preference. Good luck!
Here is what I got:
The centripetal acceleration at the equator = 4*pi^2*r/T^2
Where T = time period. For Earth, this is 24hours = 86400 seconds.
R = radius of Earth. This is 6400 km = 6400000 meters
Therefore, 4*pi^2*6400000/86400^2 = 0.03 m/s^2
Since the acceleration due to gravity is approx. 9.81m/s^2, then you would weigh only about 0.3% less at the equator than at either the North or South poles.
Is that right? I feel like I am missing something. Any help would be much appreciated! Thanks so much!