The total amount of energy in a system:. As noted above, one example is a lump of coal, which when burned will release a certain number of joules J of energy, mostly in the forms of heat and light. Another, perhaps more common example, is that it takes about 1 joule to raise an apple by 1 metre. Energy used up over time:. Most electrical devices have their power consumption rated in watts W. A watt is a rate of energy consumption of one joule per second. So, if you have a light bulb in your room that's rated at W it's using energy at a rate of joules every second.
To go back to the second example in the first bullet point, lifting an apple by 1 metre every second would mean that there is a power output of 1 watt. For most people this would be quite easy and could be kept up for quite a long time, but now imagine lifting apples a second, i.
This, in human terms, is a large power output, but nothing special for many electrical devices. It's not uncommon, for example, for a kettle to be rated at W or more.
That's a lot of apples! So, to summarise, energy comes in many forms, and it can be transferred from one system to another. The basic unit of measurement for energy is the joule. Another and simpler way of defining mass is to say that it's the total amount of matter in an object. Mass is measured in kilograms kg. Weight is actually a measure of the gravitational force pull felt by a body and is measured in newtons N note that scientific units that are named after people are almost always in lower case when spelled out fully, hence newtons and not Newtons, watts and not Watts etc.
For example, astronauts walking on the surface of the Moon have the same mass as on Earth but only weigh one sixth of what they would do back home. As with energy, the idea that mass is common to all objects is relatively new and again dates back to around the nineteenth century. Before that time different solids, liquids and gases were all thought to be only loosely connected in conceptual terms. As with energy, we now consider that mass is neither created or destroyed, but is merely changed from one form to another, e.
We use the letter c to represent the speed of light. In a vacuum, such as space, it travels at close to , miles per second , km per second. Up until that time everyone assumed that the speed of light was infinite, i. However, during the seventeenth century it was discovered that there was a problem in calculating the orbital time of Io, the innermost moon of Jupiter. It sometimes took "too long" to make an orbit of the planet and at other times was "too quick". The Metre How long does it take to walk around the Earth?
The Candela How many candles are as bright as a light bulb? The Mole How many atoms are there in a diamond? SI Derived Units Just what is a henry? The Second Is a second always a second? The Kelvin How hot is a bolt of lightning? Deriving - Basic Deriving - Advanced.
Sa nu spun ce fel de IQ aveti… Intr-un top al celor mai inteligenti oameni din toate timpurile, top in care se gasesc cei mai mari oameni de stiinta ai planetei precum Isac Newton, Thomas Young, Galileo Galilei, Leonardo da Vinci, Albert Einstein se afla pe locul 2 cu un IQ intre , pe primul fiind Johann Goethe cu un IQ intre Sunt oameni de stiinta, nu au scos nici un album, nici pe la nunti nu canta…pe bune!!!
Sa vb asa ceva despre un geniu…. Ma opresc aici! Nu vreau sa jignesc. Cam vechi comentariul facut de domnul lautar, dar in speranta ca poate il va vedea… speranta moare ultima, dar moare. Admir onestitatea dumneavoastra, dezamagit de naivitatea dumneavoastra …. Buna ziua prieteni! Refertor laTRG. Einstein ar fi intirziat evolutia stintei cu 50 de ani.
Daca e cazul mai revin cu date din istoria stintei. Salut prieteni! Scuze pt. Eroare premiul Nobel pt. Primul care a prezis efectul fisiuni bombei atomice a fost fizicianul german Otto Hann si inca un fizician nu il retin numele iar materialul pentru bomba atomica afost produs in oasulCicago reactorul find const. Despre ce fluid ar putea fi vorba?
Nu cumva este vorba de acel fluid perfect si inponderabil, pe care relativitatea il respinge din teorii si-l exclude din univers. From the three base layer: top, buttom and Board I generate till 5 files: - Top standard, path for 0,6 mm - Top small, path for 0,25 mm - Bottom standard, path for 0,6 mm - Bottom small, path for 0,25 mm - Border Once configured, CircuitCam perform all these operation by just few mouse clicks. The isolation calculation is very fast and accurate much faster and better than Coppercam.
The results can also be edited. The five layer must be configured as long as the tools to be used. I use a tricks to speed up the procedure. Once made the first project, a make a copy and then I replace all the layers data with the new one, all other assignment are kept and the generation are greatly speed up. Cimco edit let you check the gcode generated and simulate the final result.
At the beginning it is a must, it let discover errors or mistakes in the Gcode or procedure used to do it. The attached picture is a sample double side PCB. Additional notes CopperCAM basically perform all these operation, is small and quite easy to operate and cheap.
Unfortunately, some drawback are very annoying and serious if you want to make good PCBs. The isolation path is not accurate and even worst non optimized, do not support different size tool, editing is poor, drilling depending the way is generated is not sorted or not referenced to the coordinate. Hi, looks quite good. I have been working with PCB milling also, still doing it for very small boards.
I have similar experience, especially leftover copper whiskers are a big problem. Usable time of the bits i also not tooo good. This is mostly faster and gives better results. It is cheaper also and you can etch 5 mill isolations , which you cannot mill anyway It is not difficult but, it takes some time to discover.
I am quite busy at the moment, but give me some days and I will tray to post the configuration file. I have collected some information. But I want to get some Practical suggestion from you as you are a user.
Please suggest me regarding Company, Price, Quality and any other information you deem required for the CNC Milling and Drilling Machine you suggest - if possible on your part. Your kind cooperation will be accepted with gratitude.
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