physics

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Which Way Do Your Feet Roll?

Ω April 23rd, 2010 Ω Tagged Dirty Dozen, food safety, oatmeal, organic, physics, running, Saratoga Peanut Butter Company, strawberries Ω 39 Comments

New PSA: Your foot health is VERY important. You’re asking them to do a lot: running around from appointment to appointment, standing in line, even giving a well-placed kick every so often. Those puppies take a lot of abuse.

Did you know that when you run, your feet strike the ground at a force of three to four times your body weight? So, let’s take me for example:

F = mg
F = (54.5 kg) x (9.8 m/s2) (give or take a few decimal values)
F = 534.5 kg.m/s2 = 534.5 Newtons (with rounding error)

So, just loitering around, I’m exerting a force of 534.5 N on the Earth (and the Earth is pushing back on me with the same force, but for the sake of simplicity, we’ll ignore that little detail). So that means that when I’m running, I’m exerting a force of 1600 to 2100 Newtons! No wonder my feet hurt! Even if you don’t run, you exert a lot of force while walking.

I thought about force while I was running today (what? don’t you all think about stuff like that?), and how, gosh darn it, sometimes my feet just HURT. Especially the outsides of my feet. When I examined my sneakers a little closer today, I discovered why the outsides of my feet hurt the most:

See how the outside edge of my right sneaker is worn away? Here, it’s more apparent in one of my everyday walking-around shoes:

I’m a classic supinator, meaning my feet roll to the outside when I’m walking and running. Apparently, supination is not as common as overpronating, because I can’t find many shoes specially designed to correct supination. I’ll keep searching.

What? You want to know how big my feet are?

Yes, that IS dirty old grass hanging down from the sole.

My feet are a size 9. I’m 5′ 6″, so my feet aren’t THAT big … but, as I mentioned before, my nickname at a former place of employment was “sled foot”. I just think of my big feet giving extra leverage while I run. Eat my dust, sukkahs!

Let’s talk about food a bit.

Oh no!! It’s the last of the Chillin’ Chocolate! The best OIAJ I’ve ever had, but still … *tear*

With a creepy hand lurking in the background.

My sister D sent me this cute little Dirty Dozen cheat sheet that you can print out and take with you to the supermarket:

[source]

The Dirty Dozen are the 12 items of produce that have the highest level of pesticides. I talk about what produce to buy organic and what to buy conventional in this post from way back when. The guide above is great, especially concerning spinach. If you buy spinach in those “triple washed” tubs, don’t be deceived – spinach tested the highest for coliform bacteria of any leafy green, even spinach that was already “washed”. So, wash wash wash your spinach!

(Click on the “coliform bacteria” link if you really want to see what coliforms are. I’ll give you a hint: poopy.)

Have a great weekend, everyone! See you all on Sunday!

Q: Which way do YOUR feet roll?

» Filed under Exercise » 39 Comments

The Lonely Mountain

Ω March 7th, 2010 Ω Tagged chocolate, Deer Valley, oatmeal, physics, skiing, Utah Ω 16 Comments

Well, not so lonely – Utah has a lot of mountains!

But, let’s back up a little. Saturday morning began with a hearty bowl of oatmeal with a little of my favorite topping:

After some last-minute packing and dropping off the dogs (tear … :( ), we headed to the airport.

~~Goody-two shoes~~ Peter catching up on some schoolwork:

Check out the plane we took for the first half of our flight:

The plane had a row of one seats along one side of the plane and a row of two seats on the other side. This plane was tiny! Peter is tall, but he’s never rubbed the top of his head against the ceiling of an airplane – until now.

I guess the static electricity of friction between hair and ceiling caused a build up of same sign charge in his hair strands so that they repelled each other:

Physics in action.

I was dozing off during the flight until all of sudden I heard a flight attendant say “cookie”? I pulled myself out of my fog and saw that they were handing out Biscoff. Of course, I thought of Kath as I was chowing down.