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Windmills generate electricity by the spinning blades. Why can't EV vehicles recharge their batteries from their spinning wheels? Is that too hard?

They do. It's called regenerative braking. The only time you can practically recover energy from the wheels is during braking. Taking energy from them slows them down. If you do it while they are ...
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12 votes
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Is the bigger wire section always better from the electrical point of view?

Is there any case or application where using a wider cable section is worse? Yes, it may create the wrong characteristic impedance. Here I'm thinking cable (as per your question) and coaxial cable ...
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8 votes

Is the bigger wire section always better from the electrical point of view?

In high voltage AC applications, where the skin effect is significant, it is sometimes better to use multiple conductors over one larger one. A previous question related to this: Why are the high ...
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5 votes
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How does a 4-20mA bus powered sensor work?

A two-wire 4-20mA transmitter has its own voltage regulator to be able to handle high loop voltages, uses less than 4 mA for its own operation, and has a circuit to adjust the additional current that ...
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5 votes

Why mAh is constantly going higher?

mAh measures the total charge which has passed through some point over all time. It is like a turnstile counter for electrons. So mAh is a great way to keep track of capacity, just the way a turnstile ...
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4 votes

Why mAh is constantly going higher?

The mAh reading on your meter is a measure of the total energy used since the meter was last reset. It does not indicate the capacity of your battery.
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4 votes

Can I run resistor at a power higher than rated if I have external cooling?

If you need a reliable design, no. Indeed you might not even get that, as the rating depends on ambient temperature and free airflow, and if those are in limited supply, you don't get the datasheet ...
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4 votes

Can I run resistor at a power higher than rated if I have external cooling?

It’s up to you to evaluate whether it’s okay. The manufacturer may not support you, since you are operating outside of the absolute maximums for the part. If you wanted to be on solid ground, then run ...
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4 votes

Is the bigger wire section always better from the electrical point of view?

Is there any case or application where using a wider cable section is worse? This can be generalized: is there any case or application where using a more resistive wire is preferred? Obviously: yes! ...
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2 votes

Is the bigger wire section always better from the electrical point of view?

Obviously, there are disadvantages such as cost and environmental impact. These alone call for always choosing the correct wiring dimension, which is generally defined as the smallest cross section ...
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2 votes

Peak switching power in MOSFET as seen in LTSpice, and reduction using snubber or gate resistor

Yes, this is a fine way to do it, given all the usual caveats of power electronics design, including accounting for stray inductance of the switching loop, peak and average power dissipation, thermal ...
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2 votes
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Peak switching power in MOSFET as seen in LTSpice, and reduction using snubber or gate resistor

but I'd like some confirmation that these transients might be ignored. Absolutely not. They cannot be ignored but, you can easily check to see if the device you have chosen is suitable. Open the data ...
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2 votes
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How much power passes through the shunt component of a high-pass Pi or Tee filter?

You are lacking several terms, and so you aren't asking quite the right question, or providing sufficient information to base an answer on. There are a few things that can be measured, which can be ...
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1 vote

Windmills generate electricity by the spinning blades. Why can't EV vehicles recharge their batteries from their spinning wheels? Is that too hard?

The motion of a car is a form of energy, and to get the car moving in the first place that energy had to come from somewhere, either fuel or batteries. If your car is electric, energy stored in the ...
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1 vote

Is the bigger wire section always better from the electrical point of view?

There are a number of things that have already been discussed about transmission line effects and capacitance, but a MAJOR one occurs in ordinary mundane 'nearly DC' mains wiring. If you make the ...
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1 vote

Can I run resistor at a power higher than rated if I have external cooling?

Try water cooling as it will try to go to 200'C in air
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