Help with distance between cities?

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Homework Help Overview

The discussion revolves around calculating the distance between Panama City, Panama, and Pittsburgh, Pennsylvania, based on their latitudinal positions. The problem is situated within the context of spherical geometry, specifically focusing on the relationship between angular measurements and arc lengths on a sphere.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants express uncertainty about how to apply the given angular measurements (9° N and 40° N) to find the distance. There is mention of needing to determine either the arc length (S) or the radius (R) of the Earth. Some participants consider the assumption of the Earth being a perfect sphere for their calculations.

Discussion Status

While initial posts reflect confusion regarding the necessary calculations, one participant indicates a potential resolution by identifying the Earth's radius and converting angles to radians. This suggests a shift towards a more productive direction in the discussion, although no consensus has been reached on the method.

Contextual Notes

Participants are working with limited information, primarily focusing on the angular positions of the cities and the assumption regarding the Earth's shape. There is an implicit need for clarity on how to utilize these angles in the context of the problem.

theintarnets
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Homework Statement


Find the distance in kilometers between each pair of cities assuming they lie on the same north-south line:
Panama City, Panama, 9° N and Pittsburgh, Pennsylvania 40° N

Homework Equations


All we talked about in class is that θ = S/r

The Attempt at a Solution


I'm really not sure what to do... I assume I'm supposed to be solving for s or r, given that θ1 is 9 and θ2 is 40 but...I'm still not sure what to do.
 
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theintarnets said:

Homework Statement


Find the distance in kilometers between each pair of cities assuming they lie on the same north-south line:
Panama City, Panama, 9° N and Pittsburgh, Pennsylvania 40° N


Homework Equations





The Attempt at a Solution


I'm really not sure what to do...

The distance between them is along an arc - if you assume the Earth is a perfect sphere - we commonly do.
 
So what am I supposed to do? All I'm given is 9 and 40. I know I need S or R, but I don't know how to get them.
 
Nevermind, I think I've got it. Apparently the radius of Earth is 6400 km. So I converted the given θ's to radians and then solved for S for the both of them, then subtracted to get the distance between the two :D Thanks for the hint, PeterO
 

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