Engineering

Ideas 💡 for a perpetual motion generator that harnesses gravity to create a positive energy output 🤔 EDIT: lesson learnt, always research your idea before starting a topic about it 😅 even with positive and negative mass chasing each other, its impossible to create a positive energy output.

Hello.I am a aspiring engineer or physicist or computer scientist.While in high school(8th grade I am 13) I have had multiple chats with individuals about the topic of FUTURE LIKE SPACE TRAVEL.I don't mean flying saucers but spacecrafts that use magnetic levitation to leave earth's atmosphere , or Negative mass built spacecraft .I was wondering what are the possibilites of such technologies.

Hi everyone ! In shops, one remaining Covid contamination path is money. An answer is to allege that money doesn't host the virus, I read that. Or we can try to tackle the problem. UV light is known to destroy virusses, including Sars-Cov2. UV LED are available for near-ultraviolet Hg wavelengths, compact, reliable, efficient. This could irradiate the money between the cashier's and the customer's hands, in both directions. The rest is mechanical design, still imprecise. The apparatus must stop the UV from exiting but irradiate both sides of banknotes and coins. Both users could introduce the money at the top, say between a pair motorised soft rolls, a…

Is it possible to decrease the systematic error to zero,approximately zero the ideal state,if we consume that the systematic error occurs because of the temperature difference in the room where we are meausiring,the instruments are getting older when we are using all the time.For example if we are at a room which we can nearly keep the temperature difference constant,and we use only new bought instruments,can the systematic error become to zero.Is that possible to explain theoretically and practically?

I'm trying to pre-bake dry a developed photoresist. Generally what temperatures can soft photoresists handle? can a soft-baked photoresist handle warm water? Thanks

My company has an old Hitachi V212 oscilloscope. I found two online manuals one saying I needed the AT-10AQ probe and another saying the AT-10AJ probe. In our office I only found two AT-10AR probes, one working one broken. Could someone potentially elaborate the differences? Are there ways I can use different probes if i can identify the differences, and account for them in my results? Also Ive seen a lot of 1x/10x probe nomenclature, does that refer to the "10" in the probe name, and is that reflective of the Gain? Thanks

I am using manual rotameters to mix concentrate and water in-line. do I need to be concerned if the pressures of each stream are different? How can i be sure that backflow does not occur if my water line is higher pressure than my concentrate. what kind of range of mixing can I achieve? Can i mix 0.1mL concentrate with 100mL water if the pressures are the same? how much will variation in house water pressure effect the ultimate accuracy? Thanks

Washing machines squander electricity to heat water, dishwashers too. That much: (0.4m)3 = 64kg water from +15°C to +40°C is 6.7MJ=1.9kWh, in two passes 3.7kWh. Heat losses during the process make it worse. At variable 0.3€/kWh it costs 1.1€, just once a week is 170€ in 3 years, ouch. To +90°C it's 30MJ, in two passes 11kWh and 3.3€. Every second week costs 260€ in 3 years. Blistering barnacles! We can fill the machine completely, and when possible wash in a single pass less warm, to save electricity, washing powder and water. I've just bought 6 bed sheets which the saved electricity will pay in 3 years, better than a savings account. But what can technology do?…

There are a host of inexpensive HD antennas for sale that seem to promise reception that seems beyond possible. I have always understood the broadcast T.V. signals are pretty much line-of-sight or about 35 miles before a tower is needed to get above the curvature of the earth. I recently watched a comercial that claimed 100 miles reception with one of those non-elevated, mount indoor, H.D. antennas. Two questions: 1) Is that 100 mile claim an outright lie? 2) If not an outright lie, what specific electronic technology would make 100 mile reception possible? If you choose to answer my questions, please list your qualifications (to weed-out pre…

Hi. There is the claims of what is better or not; the copper, the iridium, the iron, the platinum ones... Are the expensive metals used in tiny amounts only on the spark eroding prone tips or is there a larger component using such ? I would suspect the industry would just save the $ and barely coat/plate only the critical surfaces. What do you know ?

Hello everyone, I am very curious and unsure, today I watched a documentary about Hydrogen and the earlier attempts of a Hydrogen Economy. I am really fascinated! But I don't understand why the Hydrogen Economy always failed. Already in 1874 wrote Jules Verne that hydrogen will replace coal in the future, 100 years later in 1980, after the Chernobyl catastrophe the Hydrogen Economy had a new climax and it failed again, and now researchers shout out again : The Hydrogen Economy start now! - What changed? - Why can the Hydrogen Economy now be successful?

Does anyone know how small a nuclear fission explosion can be for nuclear pulse propulsion? It seems that you would want a "tiny bomb" with the smallest mass possible. You want to give enough push to your pusher plate but you don't want the tiny bombs to add too much weight to your space probe. The smallest I could find is the Davy Crocket: "The M-28 or M-29 Davy Crockett Weapon System was .... one of the smallest nuclear weapon systems ever built, with a yield between 10 and 20 tons TNT equivalent [1/1000th Hiroshima]." https://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device) ONE of the smallest? What are the others? By now there must be smaller …

Hello, I am an engineering student. I have a question for you. Let us consider, we have an electric motor and it is being supplied the electric current. Thus it is converting the electrical energy into mechanical energy and we are getting the rotational motion at the end of the shaft. Now, what if we connect another motor(to be specific a generator) to the end of the shaft and it is further connected to store the energy in batteries, is it possible to convert the energy completely and store it? maybe not due to the core losses in both motors. But, what if we attach a set of gears at the shaft such that, the speed of rotation of the second motor is greater than t…

Is it possible to reverse play a sound file? Sound file formats viz .wav,.mp3,.aac etc. Do the methods will vary for different sound file formats? Thanks & Regards, Prashant S Akerkar

I do believe hydroelectricity has a great future and presently most of the industries are relying on it. Though i didn't had much knowledge of hydroelectricity principles before, but i found one very good article on internet below : https://www.scienceclear.com/hydroelectricity-a-massive-source-of-electricity-2020/ Must have a look!!

I am looking for single substrate inspection and/or metrology services for wafers and photomasks, does anyone have a recommendation? My company does not have the capital to purchase a tool. Thanks

I'm trying to understand what the perspectives electrogasdynamic generators could have. http://webcache.googleusercontent.com/search?q=cache:R6u9G8jzBIYJ:www.iaea.org/inis/collection/NCLCollectionStore/_Public/38/114/38114997.pdf+&cd=1&hl=en&ct=clnk&gl=ca http://www.freepatentsonline.com/3723777.html https://www.geographynotes.com/energy-management-2/generators/electro-gas-dynamic-generator-with-diagram-energy-management/4192 And have questions to those who understand the principles of their work quite well: 1) What are their efficiency, power density and electric current density limitations? What could be done to improve these par…

Right now, amid the covid-19 global pandemic and climate change and so much more, locusts are also decimating crops and amplifying starvation across the African continent. They’re everywhere and they’re hungry and people are hurting with hunger. What would it take to catch the locusts en masse / at scale and use then as a source of protein to feed the hungry? Essentially: Prevent them from causing starvation and use them to solve starvation. I’m thinking of something like a giant fishing net for the air, but am sure there are far better ideas (am not sure, however, humans can even eat locusts, but they seem close enough to crickets). Bonus points if any s…

Rather than people going through subway cars and busses disinfecting surfaces, have intake and output vents for each car. You attach a vapor hose to the input vent and fill the car with pressurized disinfectant vapor. After the virus is dead, open the output vents and remove the vapor from the car by blasting warm air thru the car, from intake to output vents. Any complaints?

Hello everyone! Copper tape is a thin copper band over adhesive tape, commonly used against electromagnetic interferences, seemingly also as a snail repellent. It used to cost a shiny penny for no reason, but the Chinese remedied that, check eBay and Alibaba. I should (I didn't try) be excellent to build antenna prototypes or indoor antennas, also outdoor antennas if protecting the conductors. Quickly assembled, modified, adjusted. Complete the contacts with the soldering iron. If the tape shall adhere on a flat item, then panel antennas, dipoles and dipole arrays, patch antennas, Uda-Yagi spring to mind. An optional second plane would constitute a reflecto…

So firefighters, when they need to get to a lower floor in a hurry, slide down a pole. They let gravity to the work, rather than their legs. I'm kind of left wondering; wouldn't this be a good alternative means of transport, to locations of a lower elevation? Rather than having a bunch of asphalt-paved roads leading from something high-elevation (eg. an airport) to something low-elevation (eg. a seaport) why not have; instead of and/or in addition; a pole or large slide that lets gravity do the work? Here are my two proposals. 1. A thick metal cylinder, that would be secured on each end, from which customers could put their arms and leg…

i need to regulate the air flow into an industrial oven ,and to do so : i have an asynchronous motor which i will connect to a frequency converter (excuse my english if i dont use the correct technical terms i studied and work in a french country ) and then regulate the speed of which the ventilator rotates .and this is where i need help i need to find the connection or the equation between the rotation speed of the propellers and the speed of air that s being propelled so that i multiply the latter by the section of the airway and finally regulate the air flow . ps : i know i can just use a sensor to calculate the airflow and regulate it directly but that is n…

What will wireless communications look like in 50 years? Is there any new ideas on how is it possible: 1) Reduce amount of the base stations (cellular towers) quite a lot. 2) Increase the data transmission rates. 3) Reduce radiation. 4) Increase the distance signal travels and reduce power consumption? Is it possible at least theorize that somewhere in the distant future we may have wireless communication with no need for the base stations and subsequently free of cost, basically?

Hi everyone! Rocket nozzles must be short and light but make the flow as parallel as possible at the exit. Further demands exist in the atmosphere. The eggcup shape answers that but needs numerical optimisation. The thermodynamic state itself isn't algebraic, and a single point takes an effort to a PC. Dozens of chemical equilibria shift with T and P, notably 2CO + O2 <-> 2CO2. Condensation and solidification over the expansion, typically of Al2O3, worsen everything. The heat capacity depends heavily on the temperature. And limited heat exchanges between droplets and the gas would be useful to model. One common assumption is that the chemical composition s…

Ages ago, I was fooling around with one of my 3d programs and I came up with this rather bizzare idea of making a hang-glider that would have the ability to produce its own power to keep airborn with a pilot. This attempt is alot different than a normal hang-glider though. The wing would consist of a flexible solar panalled core and would also consist of inflated cells, I figured helium would be the best bet, since its so light. The power from the solar panels would be directed into maybe an electric engine mounted to the pilots rear. http://homepage.ntlworld.com/mplayer/sglider.jpg It was just an idea, and I havent a foggiest idea wether it would be possibl…