Normally, the thingies you turn to get anything from cold water to hot water and everything in between out of the shower head. Turn them up, and you have greater water presure, turn them down and you have less. More hot water normally means hotter water, and more cold water usually means colder water. Turn them both down all the way to turn the shower off.

RANT

I've heard than many many people out there sing in the shower. I don't. I think. I take a fifteen or twenty minute shower, and 70% of it is just standing there and thinking about things. Thinking about forgetting a girl. Thinking about whatever we're talking about in physics. (Ah. Physics, the best class ever) Sometimes I think about how the first thing I want to do out of college is to participate in a junkyard war. But a thought came into my mind the other day, and I've thought about it a little here and there whenever I'm in the shower, and now I'm going to share it with you.

Whenever I want the water to get hotter, I always accomplish this by turning the cold knob down!!! (note the exclamation marks for emphasis) Now, I suppose most people wouldn't really care, and just continue singing whatever they sing in the shower, but the thought always gnawed at the back of my mind whenever I'm thinking in the shower. So here's my explanation...

Some givens: usually the higher the percentage of hot water, the warmer the water is. Also, I'm assuming that the water pressure is high enough for your liking, and it's not going drip drip or sandblasting your back.

Let's say I start the shower with warm water. That is, 50% of the water is coming from the hot valve, and 50% is coming from the cold valve. Each valve has 100 cubic centimeters of water flowing through it a minute (I actually have no idea how much water comes out in a minute. If anyone knows some statistics, I'd gladly take a /msg!). So, the water is 50/50 hot/cold, and 200 cm^3 total amount of water flowing through the showerhead, and onto my thinking head..

What happens if I turn the hot up by ten so that 110 cm^3 is coming from that valve, and just 100 cm^3 from the cold? (Interesting question, eh?) Well now the water is 52.38% hot and 47.62% cold.

Now, let's try the opposite. I turn the cold down by 10 cm^3. The total amount of cold water coming out is 90 cm^3, and the hot is still at 100 cm^3. So now, the water is 52.63% hot, and 47.37% cold.

So, in conclusion, I can get the water hotter in fewer rotations of the shower knobs (and thus saving precious milliseconds of time so I can think more about stuff like this) by turning the cold down, rather than turning the hot up.

Now go forth into the world with this knowledge and figure out if there is a practical application for this. Now why I think about something like the shower knobs rather than singing is beyond me. I hope I'm at least somewhat normal anyway. I have no idea if anyone shares the same thoughts as me, but I hope I'm not committing XP suicide. (sometimes I can just never tell...)

And you also conserve water with this method! Thanks C-Dawg for pointing that out. Quick and easy hot water while at the same time saving the planet!!! Hot diggity damn!