What Is Electricity? (2013)
learn.sparkfun.com
What Is Electricity? (2013)
1–10 of 48 posts
Re: What Is Electricity? (2013)
#2A thread from 2015: https://news.ycombinator.com/item?id=10400123
Re: What Is Electricity? (2013)
#3One aspect of electricity I think is useful to emphasize is that electrons in a conductor move more like the steel balls Newton's cradle (that toy you may have seen where a ball strikes one end of a line of balls, and nothing moves except the end ball, or you can pull back two balls and then only two balls will move, and so on). This can help with intuition about the distinction between "holes" and electrons, and how energy can flow with holes (which is quite counter-intuitive, I think). In terms of mental model, the ratio of holes to ambient electrons is sometimes useful to think about, as this is fundamental to computing current limits of conductors.
There is a diagram (an animated GIF) about half-way down that sort of implies the newton's cradle method of moving charge, but I don't like it because it's not clear enough. Also, I see current as more of a fixed cloud of valence electrons with holes moving through it - which is a very different intuition than what this diagram implies.
Re: What Is Electricity? (2013)
#4One aspect of electricity I think is useful to emphasize is that electrons in a conductor move more like the steel balls Newton's cradle (that toy you may have seen where a ball strikes one end of a line of balls, and nothing moves except the end ball, or you can pull back two balls and then only two balls will move, and so on). This can help with intuition about the distinction between "holes" and electrons, and how…
Looks like what you are describing is a model of the conductivity in the valence band (of a semiconductor). In the conduction band of a metal electrons move freely, their forward mobility being impeded only by heat.
Re: What Is Electricity? (2013)
#5One aspect of electricity I think is useful to emphasize is that electrons in a conductor move more like the steel balls Newton's cradle (that toy you may have seen where a ball strikes one end of a line of balls, and nothing moves except the end ball, or you can pull back two balls and then only two balls will move, and so on). This can help with intuition about the distinction between "holes" and electrons, and how…
Looks like what you are describing is a model of the conductivity in the valence band (of a semiconductor). In the conduction band of a metal electrons move freely, their forward mobility being impeded only by heat.
Well, maybe the part about the holes. But even wikipedia mentions newton's cradle! https://en.wikipedia.org/wiki/Electrical_resistivity_and_con...
Re: What Is Electricity? (2013)
#6I teach high school physics. Here's my notes/textbook on electricity with simulations and equations rendered in LaTex.
https://landgreen.github.io/physics/notes/circuits/electrici...
Re: What Is Electricity? (2013)
#7One aspect of electricity I think is useful to emphasize is that electrons in a conductor move more like the steel balls Newton's cradle (that toy you may have seen where a ball strikes one end of a line of balls, and nothing moves except the end ball, or you can pull back two balls and then only two balls will move, and so on). This can help with intuition about the distinction between "holes" and electrons, and how…
The distinction is between the speed of propagation (e.g. how fast between a light switch flipping until lighting the room) and the physical movement of subatomic particles through the wire.
Re: What Is Electricity? (2013)
#8One aspect of electricity I think is useful to emphasize is that electrons in a conductor move more like the steel balls Newton's cradle (that toy you may have seen where a ball strikes one end of a line of balls, and nothing moves except the end ball, or you can pull back two balls and then only two balls will move, and so on). This can help with intuition about the distinction between "holes" and electrons, and how…
Here's my take on a cartoony conductivity simulation. I've got three models: conductors, semiconductors, and semiconductors but with holes.
https://landgreen.github.io/physics/notes/electromagnetism/c...
Re: What Is Electricity? (2013)
#9Just amazing! Imagine all the physics and knowledge from multiple sciences, disciplines and fields are used when someone tells Amazon Echo to turn on a charger or socket that’s connected to a phone or laptop.
Echo -> ISP wires —> Undersea Cables —> Amazon Servers -> Back home -> Electricity flow
And this is so super high level
All of these devices on the way are powered by electricity from dams, solar, wind etc. Before voice to speech hits or data is read. Processors and hard disks must do so much heavy lifting
It’s surreal the level of abstraction we are surrounded by..
Re: What Is Electricity? (2013)
#10I teach high school physics. Here's my notes/textbook on electricity with simulations and equations rendered in LaTex. https://landgreen.github.io/physics/notes/circuits/electrici...
I haven't gone through all of your notes yet, but this would've been a godsend to go over in highschool before I started my EE classes in college. It was always obvious which students had been lucky enough to already cover the material.