Science & Mathematics - 25 September 2007

2007-09-25 03:27:19 · 11 answers · asked by opjames 4 in Astronomy & Space

What kind of microcontroller should I use for a VERY simple 2 wheeled, move-forward, move-backward, turn-around, piece-of-crap robot? It's my first robot, but I know quite a bit about robots, just nothing about the difference between microcontrollers and what I'm looking for in one.

2007-09-25 03:26:24 · 5 answers · asked by Rogue Engineer 1 in Engineering

Please and thank you (: (: xx

2007-09-25 03:25:51 · 5 answers · asked by Anonymous in Physics

2007-09-25 03:25:13 · 1 answers · asked by jjacob 1 in Physics

I have a hair straightner which works very well with my hair. I live in India. I know that in USA there is different frequency. So will I able to use my straightner in USA with an adaptor? What should I do for this? Anybody knows how this adaptor will work or not or any details helping me??

2007-09-25 03:24:18 · 3 answers · asked by Anonymous in Engineering

4x+3y/2 + 2x+2y/3

2007-09-25 03:23:28 · 9 answers · asked by Anonymous in Mathematics

2007-09-25 03:22:50 · 5 answers · asked by kevin1245 1 in Earth Sciences & Geology

Steps please. I understand the integrating factor is y but I don't know how it is determined. Thanks.

2007-09-25 03:21:55 · 3 answers · asked by Lobster 4 in Mathematics

2007-09-25 03:21:42 · 5 answers · asked by Anonymous in Botany

How does log 1.10 = 0.0953?
why does log (e^x) = x?

2007-09-25 03:20:37 · 4 answers · asked by Anonymous in Mathematics

2007-09-25 03:19:38 · 5 answers · asked by stefan p 1 in Chemistry

A mixture consisting of 11.3 g of calcium fluoride, CaF2, and 13.0 g of sulfuric acid, H2SO4, is heated to drive off hydrogen fluoride, HF.




CaF2(s) + H2SO4(l) ==> 2HF(g) + CaSO4(s)




What is the maximum number of grams of hydrogen fluoride that can be obtained?

2007-09-25 03:19:19 · 3 answers · asked by Joe C. 1 in Chemistry

2007-09-25 03:18:40 · 3 answers · asked by sakura_ch4n 2 in Zoology

2007-09-25 03:16:00 · 9 answers · asked by Anonymous in Mathematics

Class XI Physics...

2007-09-25 03:14:26 · 2 answers · asked by invincible_perfectionist 1 in Physics

That x=0?

2007-09-25 03:08:08 · 4 answers · asked by XRAYDELTA1 2 in Mathematics

I fully know and understand how the Ammonia / Water absorption process works.

I even understand how the Ammonia / Calcium Chloride absorption process works.

But in their case, Ammonia is the refrigerant. It has a boiling point of -33 Degrees Celsius. It's understandable that when it evaporates, it takes away heat.

But in the water / lithium-bromide process, water is the refrigerant. I understand that the pressure is lowered to allow the water to evaporate, but how cold can it get? Will it bring down the temperature of the surrounding area to freezing?

Also, if pressure is brought down, what kind of piping is used? Doesn't it have to be strong to withstand the pressure being much higher on the outside than the inside?

2007-09-25 03:07:51 · 3 answers · asked by Abdallah A 3 in Engineering

2 adaptations please.

2007-09-25 03:06:13 · 2 answers · asked by Anonymous in Biology

2007-09-25 03:04:26 · 3 answers · asked by mike a 2 in Zoology

minute after 900 minutes.

2007-09-25 03:03:39 · 3 answers · asked by Freddie 2 in Mathematics

2007-09-25 03:03:24 · 4 answers · asked by daineyjinh 1 in Physics

hi guys, if a cell phone battery with 957mAh and 3.7V.

957mAh is the battery capacity, isnt it?

So, is it mean that the power require to fully charge the battery is (957 X 3.7)/1000000 = 0.0035 kWh ? (assume the battery is completely empty)

If it is true (need 0.0035kWh power to charge), is that also mean this is the power needed with regardless of the charging time? for example, 2 same capacity batteries may need different time to fully charge the battery, but the power it require is the same, is it truth? Because I am not sure the relationship between charging and the capacity.

Thank you very much!

2007-09-25 03:00:02 · 4 answers · asked by marco824xu 1 in Physics

1) show by means of an example that lim as x -->a [ f(x) + g(x) ] may exist even though neither lim as x -->a f(x) nor lim as x -->a g(x) exists

ANS: the limit of f(x) = 1/(x-a) has no limit as x goes to a. Neither does g(x) = -1/(x-a). However f(x) + g(x) => (1-1)/ (x-a) = 0, which is a constant so its limit exists.

2007-09-25 02:57:55 · 4 answers · asked by Arianna A 1 in Mathematics

I am trying to understand why a home made system of inexpensive parabolic mirrors linked into a smaller series of solar panels for home use is not available. I understand solar tracking issues but believe this could be overcome.

2007-09-25 02:55:19 · 4 answers · asked by joshuaelliot1970 1 in Engineering

I have discovered an ingenious proof of this claim, but the details section is too small to contain said proof.

2007-09-25 02:55:14 · 2 answers · asked by Anonymous in Mathematics

2007-09-25 02:51:58 · 8 answers · asked by Chris B 1 in Astronomy & Space

What website can i find detailed reports on solar electricity and its materials ,price,parts, availability?

2007-09-25 02:44:38 · 4 answers · asked by Mark Ju 1 in Engineering

2007-09-25 02:42:57 · 4 answers · asked by Anonymous in Biology

2007-09-25 02:38:47 · 20 answers · asked by ahmed g 1 in Geography

I have an extra credit problem for my physics class. The situation involves an electron sitting between two grounded infinite conducting planes. You need to find the E-field and the potential everywhere etc. It goes on to ask: "Why can't a similar construction be done for gravity? What would it mean to have a 'grounded' object in this case? What would you have to do to set the gravitational potential to zero in some region?" I am unable to make the connection. Help is appreciated.

2007-09-25 02:38:01 · 4 answers · asked by dave r 2 in Physics