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1

You can only measure a part of EU compliance. By using your utility meter and measuring the difference between the power consumed over say 10 minutes with the appliance on and off (with everything else in the house as off or steady as possible), you can measure consumed power. However, that's just one part of EU compliance. The other is power factor. ...


2

Your requirement that the measurement be made with equipment available in a kitchen is a severe constraint as I can't think of any way of measuring the electrical power supplied. If it's impossible to measure the electrical power in then the only other approach is to measure the thermal power out - i.e. measure the heat produced by the appliance. Given that ...


2

The easiest way would be to use an energy monitor device (the most popular one seems to be the Kill-A-Watt but there are others). They simply plug into the wall and then you plug your appliance into it. It displays instantaneous voltage, current, power, power factor, etc. and can keep total energy over time. Another option would be to buy an electric ...


2

You have a rather precise power meter in your home, which is a "gift" of the electrical power company. Turn off every other load that is connected to that power meter and do your measurement. Alternatively, you can invest $20 in an electronic power meter that is available online and in many stores.


1

The key to understanding EMP is that this is an induced effect, so you need rapid changes in magnetic field, $\frac{dB}{dt}$. In order to generate a rapidly changing field, you have to have a rapidly changing current in an inductor - as you may recall, $$V = -L \frac{dI}{dt}$$ For this rapid change in current you not only need a high voltage - you need a low ...


6

There is a much better description here of Fizeau's nineteenth century experiment. Some of the key features that enabled Fizeau to succeed: A lens to collect the light from the source A collimating lens to prevent the light diverging during its journey A large diameter beam to minimise broadening of the beam by diffraction More lenses to focus the light ...


1

The easiest way to make a suitable coil is experimental. After all, what you want is not a precision measurement of the magnet, but all you want is to generate the necessary electricity for your LED and you don't need any math for that. Simply make a coil that satisfies your geometry out of some wire with reasonable resistance. In this case, I would estimate ...


3

This looks like a combination of capillary action and evaporation. When the container starts out clean, moisture evaporates from the edge of the miniscus, thereby leaving crystals. These crystals form capillary pathways for more fluid to climb just above the crystal, where it evaporates and forms more crystal. This process repeats so that the crystal ...



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