Horace is currently converting a classic VW bug into a practical electric car for highway use with modern batteries. What a great way to learn about some of the issues associated with electric cars!
We're beginning to see the rise of electric vehicles. They have certain advantages like power train efficiency, simplicity and enormous torque at low speeds. While many people have a reasonable understanding of how an internal combustion engine works, motors tend to be a bit mysterious. Central to the mystery is understanding magnets.
I started a post about magnets as they are a beautiful example of relativity showing up in our mostly non-relativistic world. After spending thirty minutes on some drawings I decided to see if there was anything I could borrow. In the process I stumbled into two simple videos that offer a great non-technical explanation - much clearer than anything I could easily write. Video is powerful.
first how an electromagnet works:
and once you have a grip on electromagnets, permanent magnets can make sense
This doesn't get into many other issues associated with electrification, but magnets are central to motors and generators and the modern world. We wouldn't be talking about the wonders of computation and the Internet without that foundation.
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Since this is so short, I'll throw in a a bit of gee-wiz that can lead to a much longer conversation. It has nothing to do with magnetism, but is the prelude to a response to a question that came up... 'what is mass?' ...
About 0.03% of your mass comes from our electrons. Most of us have less than an ounce of electrons - for me it is about 23 grams.
You've undoubtedly heard about the Higgs particle discovered at CERN a few years ago ... It was generally explained that the Higgs field gives particles mass, but that's not quite where most your mass comes from. Your electrons get mass from the Higgs field and only about 2% of the rest of you .. your protons and neutrons ... gets its mass from that mechanism. Other things are at work and that could make a post one of these days, but in the meantime be thankful for your mass. You wouldn't be here without it.
Massless particles zip around at the speed of light and nothing else. Having mass means your particles have the freedom to travel, in theory at least, at any speed below the speed of light. This means they can travel so slowly with respect to each other than groups of them can get together. Sort of important if chemistry and biology is to happen.
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So many variations. Mixing corn, avocado and tomatoes works very well. If you have a vinaigrette you like it is really easy, otherwise the one shown here works well. If the corn is exceptionally fresh I like using it raw, otherwise grilling it is great. Mixing in a cup or so of chopped pecans makes it a main course.
Yet Another Corn Salad
Ingredients
° 2 big ears of corn (3 if small)
° 2 cups fresh tomatoes diced
° 1 ripe avocado
° 1/2 cucumber peeled and seeded
° about a cup of chopped fresh basil
° freshly ground black pepper
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° 2 tbl red wine vinegar
° 4 tsp Dijon mustard
° 2 small shallots minced
° 1 tsp sea salt
° 3/8 cup olive oil (about)
Technique
° shuck the corn for raw kernels or grill the corn lightly oiled to get a light char
° peel the avocado, dice the meat - cut the cucumber to the same size
° put the kernels, tomatoes, avocado, cucumber, and basil in a bowl. Add pepper.
° in a small bowl make the vinaigrette with vinegar, mustard, shallots, olive oil and salt. Whisk, pour over the the salad and mix gently. Adjust salt and pepper.
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