Engineering

Hi, I know how to bias a BJT transistor to operate in the active region, so that the amplifier circuit can operate as a small-signal amplifier. Two methods (i) Use biasing resistors to form a self-biasing circuit. (ii) Use diode biasing, coupled with biasing resistors. Qn1 However, how do we bias the transistor circuit to act as small signal amplifier, if MOSFETs are used instead? Design of dc biasing circuit for MOSFET as an amplifier??? I read from my textbook that we need to bias the MOSFET in the saturation region, which is quite different from the BJT amplifier dc biasing design. The relation of MOSFET in saturation region is Id = K(Vgs - Vt)^2 …

A vapor-liquid separator drum is a vertical vessel into which a liquid and vapor mixture (or a flashing liquid) is fed and wherein the liquid is separated by gravity, falls to the bottom of the vessel, and is withdrawn. The vapor travels upward at a design velocity which minimizes the entrainment of any liquid droplets in the vapor as it exits the top of the vessel. The size a vapor-liquid separator drum (or knock-out pot, or flash drum, or compressor suction drum) should be dictated by the anticipated flow rate of vapor and liquid from the drum. The following sizing methodology is based on the assumption that those flow rates are known. Use a vertical pressure …

Here are the governing relationships for the makeup flow rate, the evaporation and windage losses, the draw-off rate, and the concentration cycles in an evaporative cooling tower system: M = Make-up water in gal/min C = Circulating water in gal/min D = Draw-off water in gal/min E = Evaporated water in gal/min W = Windage loss of water in gal/min X = Concentration in ppmw (of any completely soluble salts … usually chlorides) XM = Concentration of chlorides in make-up water (M), in ppmw XC = Concentration of chlorides in circulating water ©, in ppmw Cycles = Cycles of concentration = XC / XM ppmw = parts per million by weight A water balance around the…

How to determine the mass flow rate of a gas through an orifice or leak at choked flow conditions is a question that is often raised by those unfamiliar with fluid flow mechanics. Here are the applicable equations:

Anyone interested in or involved with air pollution dispersion modeling is invited to visit the website at: ........ www.air-dispersion.com <== click here to learn about "Fundamentals of Stack Gas Dispersion" ... a very comprehensive reference book on dispersion modeling of continuous, buoyant pollution plumes. The website provides a brief description of the book, peer reviews published in technical journals, the book's complete table of contents, and other information. The website also provides access to information about the AERMOD, SLAB and DEGADIS dispersion models and other BREEZE software used by environmental professionals worldwide. Topics covered …

Hi guys! Do you know how to build an mp3 player solely from spare computer parts? If so, could you explain or link me to a site that explains? Thanks

right now i am having trouble building and placing my combustoin chameber for my engine , got any ideas or diagrams?

Check this out guys. really interesting... think about the possibilities http://edition.cnn.com/2005/TECH/10/25/human.remote.control.ap/index.html What do you think?

we've got an industrial chillar system supplying coolers in a room full of servers. We wanted to cool the room further so we added another cooler in the room to pump out more cool air. but the tempreture dint really change. So then we lowered the tempreture of the chilled water being supplied to the coolers by about 1.5 degree celcius. the room tempreture then droped by about 4 degrees celcius. Why has there been such a big decrease in temp ? or is that normal?

i have a porblem with my tesla coil. i need to know wut size wire and how many wraps i need if im using 5kv NST. right now currently i have 5 wraps of 10 awg wire. the secondary coil is 1 1/2 in in diameter and 5 in tall would u plz help me out. i think i need smaller wire

Anybody have any sort of article that sheds light on what type of facility (pictures, even), where, and what-not the quantum nucleonic reactor will be built? What they're using to produce the isomer required for it? Basically manufacturing info on it in general - it's for my Intro. to Engineering class, but so far, i've only come across the usual *gasp!* nukes for jets! -articles.

Hello hello I've got 2 problems here which are based on the same welded slender bar. I've thought about it for ages, but I'm clueless on what to do. Any help will be much appreciated.. Cheers.

I know there are some coilers out there, so here goes. I am currently using brass bolts ground to a fine point, however I'm looking for something that won't erode quite so quicly. Oh yes, and that is cheap......or better yet free.

Does there exist a limit to which a cargo carrying aircraft can be scaled up in size? For example: The Cessna 421 has a wingspan of 12m, a length of 10m, and a maximum take-off weight of 3103kg. This a common private plane. The Mcdonnell Douglass DC-9 has a wingspan of 28m, a length of 40m, and a maximum take-off weight of 55,000kg. This is a standard US military transport aircraft. The Antonov 225 has a wingspan of 89m, a length of 84m, and a maximum take-off weight of 600,000 kg. Only one exists. It was built by the soviets for thier space program that collapsed with the end of the cold war. Anyone can see the scale moving up largely between thes…

Hello. I am in need for references(i.e websites) to electronics related fields, like micro controllers, IC constructs, analogue & digital designs, VHDL, etc. Please suggest some websites/forums which has a lot of activity in electronics and the related. Thankyou.

Hello. I am at my U.G in electronics, and i have come across a disturbing scene in which i am to consider holes as particles, ie contained mass. Could someone please explain this....in a language more soothing to a novice student of electronics, is warmly welcomed

I'm building a coilgun, I intend to create a portable version after this one. I have 4 350VDC 400v surge 4200uf and 8 350WVDC, 400V surge, 3600 uF caps. There are 3 series banks, 1 for each coil. What kind of charger should i use, mains powered?

Well.... I need a help in van de graff. I am trying to make for my science exbit. Will i get 50000V with the motor of a mixer grinder(domestic grinder). 2. I have seen that the sphere of the van de graff is covered with a glass sphere and is grounded. This stuff produces a spark 'SHOW' as sparks fly from sphere to glass. how to do it?????

is it possible to model a liquid flow as a DNA molecule. Is it possible to generate the double helix nature of a DNA molecule in a liquid

I am interfacing a pic microcontroller with an electronic compass module via spi interface. The problem is the pic outputs at 5v and the compass will only handle 3v. I am thinking voltage divider for any inputs to the compass and an opamp for outputs. What is the best way to drop and increase voltage in digital circuits?

Hey guys Need some help, I have a PCB built and it doesn't quite operate as I expect it to. I have a PIC microcontroller and a couple of LEDs which should be on when it is operating. The ground and power planes are providing power to the PIC, the MCLR pin is set high and the rest of hte circuit seems to work. However, the PIC just doesn't work. It seems to burn out after awhile. Another phenomena which happened was the LEDs turned on when I brought my hand over the board, but turned off when I pulled it away. The circuit died soon after. And funnily enough, the PIC seems to be fine. I just reprogram it and put it back in, and it operates (until it die…

OK, I have an idea which is much like a Creative Zen Portable Media center. How would I go about designing something like that. I have a B.A. in EE, but approaching a project of that complexity is another matter. For that matter, I don't even know everything I would need in designing that system. Is there a computer aided system I could use? Or what about micro boards and such. Help please! Any books I could read? I have access to an extensive library.

hey! im in the middle of creating a electrostatic motor for my grade 8 science fair project. here---> http://amasci.com/emotor/emot1.html im using the pvc pipe methode to run my motor here----->http://home.earthlink.net/~lenyr/stat-gen.htm . i wanted to incorprate the Film Can Capacitor into the project also. so i got to thinking, would it be possible to run the generator,to the capactior to the motor? where by i connect the wire to the screw on the top of the film can then on to the eletric motor,would this work? OR shold i just directly connect the pvc pipe to the motor.... THANKS (im sorry in advance for posting in wrong forum i wasent sure...…

What would happen if electrons have more or less charge than it is now?

I'm thinking about GPS, and the problems with the technoledgy. What are the technical ways of finding your current position on the earth? Any idea welcome even imposible ones, I was wondering if the sun could be used. Maybe combine the suns direction with the precise time, but how acurate? but I suspect it's a little too imposible technicaly. thoughts welcome. P.S how do you spell check on these forums?