For starters, I'd buy a premade module based on the TPA3116 chip. This gives you a subwoofer channel and a left and right channel. A good reason to buy one premade is that it's difficult to design the filters with feedback in the class D amp. Also it's cheap.
You can add your own bass/treble circuit in front of the module. Also, you could replace the ...
I believe you have a handle on it. P = I^2 * R. The thermal rise in a resistive device will be the square of current. That puts the square in RMS.
This is why RMS has the relationship it does with peak. This is the AC voltage that, when applied to an incandescent light, will provide the same light, heat and service life as that DC voltage.
Figure 1. General phasor diagram for three-phase voltages. The phase to phase voltage is √3 times the line to neutral voltage.
Figure 2. In the case of a 230 V phase to neutral system the phase to phase voltage = 230√3 = 400 V.
The √3 term comes from simple trigonometry of the 120° triangles.
It's weirder than that. If you have 220V, your 3-phase is actually only 381V because triangles.
They have nothing to do with each other
The "220V" standard is a completely different electrical system than "440V". They're coming off different transformers and they serve different kinds of loads.
In actual practice, 220V is not derived from 440V, they ...
Your mistake is assuming that a raw LED is a "normal load", it is not.
Normal loads have a relatively gentle voltage/current relationship. Small changes in conditions, either voltage of the power supply or temperature of the load, result in small changes in the current.
LEDs have a very steep voltage/current relationship, a small change in voltage can ...
"Is there a device?" There is probably nothing that you can buy that will do that. You can prevent the breaker from tripping by installing a fast-acting breaker with a lower current, but that just shuts the loads off nearby rather than elsewhere.
Could you design something?" If the loads act like resistors, a device that reduces the voltage would reduce the ...
When I touch the live wire from a power socket with my bare foot on the floor, how does the circuit close (how does the current return to the supply)?
Current will flow according to Ohm's law - I = V/R.
The following is approximate and will vary with user , contact points and more, but:
You may be able to "feel" current in the 10's of uA (microamps) range,...
The circuit closes because the home "neutral" and "ground" wires are physically connected, and this connects to the Earth ground in the home (usually a copper rod driven into the soil, or a water pipe running through the ground.)
Therefore, when you stand barefoot, current can travel from the hot wire, through your body, and into the ground.
You most likely have a ground issue on your board (non-continuous ground that is linked through the MCU) or somewhat connected the ground of the scope where it shouldn't be.
Your PC is most certainly grounded (sometimes, for laptops, it can be grounded in unintuitive ways through an external screen and through HDMI cables for example).
Your scope and ...