## More Maths. No Sweat!!!

September 11, 2009

Mathspigs there are two things that stop kids doing maths. Fear & boredom. But we are going to show NO FEAR. You may find some of these equations a bit scary. I do too. But I can make some sense of some of this stuff. Here goes.

The article No Sweat. Well, not as Much as You think (New Scientist 18/7/09 #mce_temp_url#  ) highlighted research by the US army into finding an equation for how much men and women sweat. They need this information so they can calculate how much water they need to carry. Makes sense.

How do they calculate how much you sweat???

Basically, they use NUDE body mass work out how much weight you lose after exercise. Allowances are made for mass (or weight) by breathing in oxygen and breathing out water & carbon dioxide.

They can also calculate how much heat is lost when you are nude if  m  ( or m with a little dot) is your sweat rate in grams per hour.

Then things go a little crazy. Here’s one part of the equations for heat lost when dressed. I just want you too see how crazy some equations can be.  We’re not going to use it. But when you are doing studies like this you get used to such equations.

ARE WE SCARED, MATHSPIGS? No. We’re going IN to look at the results. We can make sense of them.

Thanks to Dean Van DEn Heuvel, Kyneton, Victoria for this fab math pig pic. We like happy mathspigs!!!!

When you read the table below keep in mind:

How much do you sweat????

With one more piece of data you can calculate how much you would sweat in Battle Dress Uniform or body Armor plus vest. Your surface area:

“Normal” BSA is generally taken to be 1.73 m² for an adult. ( More @ Wikipedia: #mce_temp_url#)

Average BSA values
Child 9 years 1.07
Child 10 years 1.14
Child 12-13 years 1.33
For men 1.9
For women 1.6