Answer to Question #275999 in Physics for OMAR

Question

Estimate the number of hairs on your head.

I used an interesting estimation which is to say that 1cm² = 100 hairs and to estimate the head as sphere with radius of r = 10 cm.

Am I right to tell an estimation like this?

If not what is right??

Answer 1

Yes, that's a good approximation for a school-level physics. The calculation of surface area of our head covered with hair is much more complex, but the circle with a 10-cm radius is a good approximation as well.

The information on the density of hairs varies from a person to person, it is 100 to 250 per square cm.