Cracking the Mystery of Fermi Numbers - Come Help!

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Homework Help Overview

The discussion revolves around estimating the number of hairs on a person's head, framed as a problem related to Fermi numbers. Participants are exploring methods to approach this estimation problem through reasoning and assumptions.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants discuss the need for measurements or estimations of hair density and head surface area. There are considerations about using average hair diameter and packing density to derive estimates.

Discussion Status

Some guidance has been provided regarding the estimation process, including suggestions for measurements and considerations of packing density. The conversation appears to be ongoing, with participants expressing varying levels of difficulty and engagement.

Contextual Notes

There is an emphasis on estimation and measurement, with participants acknowledging the challenges in obtaining accurate values for the necessary quantities.

Faiza
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Fermi Numbers!??

I'm trying to solve this problem and explain all my steps in my reasoning.

**HOW MANY HAIRS ARE ON YOUR HEAD?**

If anyone can help me figure this out, reply
thanking u in advance
faiza
 
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:"( ......
 
No of hairs on head is equal to;

No of hairs per unit area x Surface area of head with hair.

You need to get a value for both of these quantities, either through measurement or estimation (or both).

Claude.
 
this is hard lol
 
Using the average diameter of a hair (about 50 microns, or pluck a few hairs and measure them) you can determine a rough upper limit on the number of hairs. The actual number depends on the packing density, which I think, is not likely less than 10% coverage. So that gives you an approximate lower bound. Pick the mean to get an order of magnitude estimate.
 

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