Engineering

i am constructing a glider made from biofoam which is flexible and weak in structure and i have made wing of 30cm from that foam.now i should make it stronger by reinforcement with any strong material.what are the choices?

Hey everyone, how's it goin? I have a question. I was reading this article earlier: Link changed to original article http://www.eurekalert.org/pub_releases/2009-04/esa-gei040609.php It's talking about an electric ion propulsion engine. Does this really work? I mean seriously, I thought in order for something to move in space it had to have something to push against???!!!! For real, how does electricity push anything in space? Can someone please explain this for me -SCIFOR

i want the bullet to do high penetration intense damage high velocity wat to do

Hello, I have a project where i need to design a heat exchanger (HE) to reduce the temperature of hot air. The hot air comes in at 700K with a pressure of 1300Kpa, it will come out of the HE with the same pressure but how do i calculate its exit temperature? I know it has something to do with the HE Efficiency, which i do not know how to find. HELP!

First post! Yay! Okay, if you work with nanowires, here's the short version: What methods would you recommend to get them off of the substrate? If you don't work work with them, here's the long version: I grow nanowires around 10 microns in length and 200 nanometers in diameter perpendicularly out of silicon wafers. I then put a layer of PDMS on top, which coats them on top and in between. What I need help on is getting them off of the silicon substrate so I have a bunch of nanowires embedded in PDMS. This is difficult, of course, because of material size and the fact that the nanowires are more strongly bonded to the substrate than to the PDMS. So far, my b…

i'm a production engg. my area of interest r robotics metallurgy operation research mechanics plz someone give me a idea

I've been thinking about switching to a motorcycle because of the fact that they're so much cheaper (both to buy and to maintain) than cars. Well, I've found a nice one here. http://www.hondaofrussellville.com/new_vehicle_detail.asp?sid=03165247X7K11K2009J9I15I55JAMQ2743R0&veh=3424&pov=1184862 I know it doesn't exactly look "macho," but that's the last thing on my mind. Judging from those specs, what do you estimate the fuel efficiency for a 240lb driver would be?

Hi, Could someone please explain me what this component from the drawing means? This is taken from here: http://www.fas.org/spp/guide/china/launch/lm2c/Image2190.gif http://www.fas.org/spp/guide/china/launch/lm2c/2C_Chapter5.htm

Hello. Slowly pouring water onto a very, very hot vessel so there is instant steam production; how is that method called ? -It is not 'flash' distillation- Miguel

One soaked black towel, made of 100% cotton in same test conditions as another black 'towel' made of 100% nylon; under the sun... Which one would evaporate/dry more rapidly ? -Or is there any other better material choice with the same texture- Miguel

hi, i m new to simulation of MANET, is there any priority for Route Request,route reply in Data link layer. because lower layer will consider as the data of the upper layer control packets. pls reply me.

Can we compress gases using ultrasound produced by piezoelectric crystals? Will the vibrations compress the gas column? What will be the excitation voltage required to produce ultrasound using piezoelectric crystal?

Hi ya guys, Here is my question: In a coil with some DC current, one can think of all of the electrons moving inside as a cylinderical electron cloud, spining around the cylinder's axis. Is it equivalent to think of the self induction of a coil as the angular momentum of this electron cloud? The coil's resistance to the current's change is analogous to the resistance of an object's angular momentum to change. What do u think?

I'm trying to build an alternator/generator that has the magnets rotating inside a coil of wire (or stator) to produce HIGH AMPS at LOW VOLTS. So what causes amps vs. volts: number of coils, magnetic field strength, rpm's, what?

Imagine you wanted to send a message to your future relatives, a few paragraphs of information. Thing is, these relatives won't exist for 1 million years! How would you construct a container and place information in it that would exist intact for 1 million years? Rules are; -Has to stay on Earth -Must be self contained (no helpers looking after it) -Money is no Option -Must use available technology -Message can be of any type of material or construction/form etc 1. What materials/technology would you construct the box out of? 2. What materials/technology would you construct the message out of? :-)

Hey guys, I need to construct an amplifier circuit for a function generator I have in my lab. I wanted to use the Op Amp IC OPA541AP from Texas Instruments as this is the same chip used in the Pasco amplifiers and can work with a large amount of frequencies. I've tried looking for typical applications of this chip but keep coming back to the data-sheet for the chip which doesn't give me a amp circuit. Any help you guys give will be greatly appreciated. Thanks

why do they flood enviroments to build hydro electic dams when they could just build them in to the river beds

i wanna make a presentation on "reverse osmosis". can any body help me

Alright! So... this is my first post on this website and i need some ideas. I currently have a school project that requires me to build a mousetrap powered cars. Well, vehicle. We are allowed to use ANYTHING we want I i can say with confidence that i will have every kind of tool i might need. So far i'm going to be using a sail servo for gears (pretty good idea i think considering i'm 14 and thought of it all by my lonesome) and a lot of carbon fiber. (i love Carbon fiber.) the servo is a 1:110 ratio so for every one turn of the largest gear, the smallest turns 110 times. It should be really good considering i'm most likely going to be using 5-6 inch wheels. I'm also goin…

After having just read Larry Niven's Ringworld (A very good book by the way), it got me thinking about how one might actually go about building and living on one. In the novel, Larry assumes the ring would be about a million miles wide, and 600 hundred million miles in circumference. To keep in all the air, the Ringworld edges are about 1000 miles high. He calculated that it would take about a mass of Jupiter to create such a structure. Not only would there be virtually limitless supplies of energy, but there would also be quite a bit of space. And much sturdier than a Dyson Sphere. Now, assuming those dimensions, how would some alien or future society go about …

Hi: Please don’t get upset at me. I apologize profusely for posting something similar in a different thread. However, you will notice some difference as you read. Does a device that switches frequency [in number of Hz] with peak-to-peak amplitude [in watts-per-meter] equivalent to the Hz number of 1-Hz-photon(s)-per-second-per-meter – and visa versa -- exist? If not, is it possible to construct one? In this device, the input of a signal that has a frequency of X Hz and a peak-to-peak amplitude of watts-per-meter equivalent to Y number of 1-Hz-photon-per-second-per-meter will result in the output of a signal that has a frequency of Y Hz and a peak-to-peak a…

I am building a wind generator with a car alternator. It has a three blade 2.8 m diameter rotor made from plywood (4mm) covered with glassfiber. The altenator is driven by a fan belt and a 1: 4 pully ratio is used. Does anybody have any expirience on this kind of design or can give some advice

Hi: Does a device that switches frequency [in number of Hz] with peak-to-peak amplitude [in number of in electron(s)-per-second-per-square-meter] – and visa versa -- exist? If not, is it possible to construct one? In this device, the input of a signal that has a frequency of X Hz and a peak-to-peak amplitude of Y electron-per-second-per-square-meter will result in the output of a signal that has a frequency of Y Hz and a peak-to-peak amplitude of X electron-per-second-per-square-meter. Thanks, Green

I have a digital bathroom scale and it's quite frustrating. I think I may get a traditional spring one. I can stand on it three times and it will give me slightly different weights like this: 1st time :209.1lbs 2nd time: 208.3lbs 3rd time: 207.4lbs And, no- this WAS three times in a row over a period of 15 seconds, I was not weighing myself with or without my clothes or shoes. I had the exact same clothes on all three times. I wonder what's going on here. I want to diet but I guess I can't rely on my scale. Seems to be the best ones seem to be the more "primitive" ones like with a spring dial or the one at the Doctor's office which has weights on the weight…

For a project I need to find out if there are any solid materials that disinfect hands upon touch. I know there are anit-bacterial coatings and nanotechnology that disinfects the object, but is there anything that would disinfect whatever touches it?? Any help would greatly appreciated!