3 ms·

Sure: As I remember from my college physics course in electricity and magnetism (E&M), a series wound electric motor has, with the simple mathematical model, i

• easytiger 12y ago
  In europe, practically everyone would fly the 900 miles or take the train.
  • cjrp 12y ago
    Just to put that in perspective, 900 miles is ~London -> Vienna. 99% of people would fly/take the train.
  • graycat 12y ago
    In the US, 900 miles was just from where I was in DC, north to Pennsylvania, west to Ohio, across Ohio to Indiana, south to the town Fort Wayne in NE Indiana, west to Warsaw, IN, and then south 15 miles to the farm of the family of my girlfriend and, later, wife. So, before we were married, I drove the 900 miles often, commonly mostly at 90+ MPH, and after we were married drove it usually at least once a year, at Christmas. When we went for Christmas, we were carrying way too much stuff to fly or take a train! And when we got there, we stayed for a few days and still wanted our car to get around, to restaurants, movies, friends, more shopping, etc. In Europe, they think that a car engine with 3.0 liters of displacement is large. The engine I was using had either 5.7 liters of displacement or, in two cases, 6.5 liters of displacement. US and Europe do some things in different ways! That part of Indiana is sparsely populated. So, from the farm, the nearest airport with much in service is at Fort Wayne about 50 miles away. Let's see: The 6.5 liter car I used most often had a 2.56 rear axle ratio and at 90+ MPH got about 18 MPG. Gas cost about $0.25 a gallon. Then the cost of gas for the 900 miles was 900 * 0.25 / 18 = 12.50 dollars, $25 round trip. Heck just the taxi fare from the Fort Wayne airport to the farm would have been about that. To use a plane or train, round trip, would have meant four long taxi trips, total cost much more than the gasoline for driving my car. For trains, actually at one time the US had one heck of a rail network with relatively good passenger service. Mostly the rails are still in the ground. Actually the little cross road town three miles from the farm did have a rail line and a station -- not used by passengers, if at all, in years. Sure, at one time could have caught a train at that station and, with lots of transfers, gone to Chicago, New York, San Francisco, etc. Lots of transfers and then waiting between trains. In simple terms, in the US, by about 1955 or so, cars put the passenger trains out of business. The US still has one heck of a good freight rail network. While Indiana is sparsely populated, keep going west to Iowa, Nebraska, South Dakota, Wyoming, Montana, Idaho, etc., and we're talking miles and miles and miles of hardly a person in sight. In the US, there's density enough for trains to have a shot between, say, Richmond, VA north to DC, Baltimore, Newark, NYC, Greenwich, Stamford, Hartford, and Boston. And we do have such trains; spent a lot of money on the trains; our VP Biden spent a lot of time on those trains between Baltimore and DC; but those trains lose money. And parallel to those tracks we have airplanes -- maybe they make money, but the TSA has made airplanes a little less comfortable than either an unanesthetized root canal procedure or a barbed wire enema. "Open wide, look at the birdie, and then grab your ankles and back up to the officer .... Have a pleasant trip." "Next time it's my car; even for 2000 miles." In the US there are lots of other efforts to spend big bucks to have trains across the Midwest, north and south along the west coast, e.g., LA to SF and maybe up to Seattle, maybe between Houston and Dallas in TX, etc. Lots of efforts. For decades. For commuters to NYC, NY has trains north to Poughkeepsie and NE to Greenwich, Stamford, Hartford, or some such. At least the one to Poughkeepsie has been losing money, and now when register a car in that area have to pay a special tax to support the trains. How do we pay for roads, bridges, etc. for cars? We're supposed to be covering that out of gasoline taxes, which are not trivial. The result is called the Highway Trust Fund; it may have a stack of IOUs from loans for other purposes. I live 70 miles north of the Wall Street area which is at the southern tip of Manhattan in NYC and for a while worked in that area. I found that except in the worst of the rush hour, my car was, door to door, faster than the trains. And I was not using a high performance car. Apparently the NYC subways work well -- I can believe that. But Baltimore put in a subway, and while I was at Johns Hopkins University there in Baltimore, once was in a lecture that analyzed the welfare economics of the Baltimore subway; welfare economics is where add up all the costs and all the benefits and see for what projects the total of the benefits is greater than the total of the costs. The lecture reported the totals of the costs and the benefits, and the costs were higher than the benefits. So, from the point of view of welfare economics, the optimal decision, given that the subway construction was done, was just to brick up the entrances and f'get about it. Or, if there were some really good benefits for that subway, adding up the value of the benefits still didn't have the benefits exceed the costs. That's what happened in that case; just why I don't know. Drawing from several decades of recent history, broadly, passenger trains don't work very well in the US. There are lots and lots and lots of people who very much want passenger trains to work well here, but the golden age of US passenger trains was from, say, 1930 to 1955 or so. E.g., there are several Hollywood movies, North by Northwest, The Sting, that show something about what train travel was like then. Basically in the US, the long distances, low population density, Interstate highway system (Ike regarded as crucial for military logistics for US national security), etc. shot the passenger trains between the eyes. One biggie reason: People already owned a car, say, just to get to the grocery store, the coin laundry (people commonly had cars before they had washer/driers at home), schools, friends, etc. Another factor was that trains had a bad reputation because at one time they were seen as exploitative monopolies. To push back, we got the Interstate Commerce Commission (ICC) with a lot of economic regulation of the trains. If a road needed a bridge over some train tracks, then maybe the train company was asked to pay for it. The unions saw the train companies as soft targets and, with the help of Congress, took advantage. So, by 1955 or so, many people in the US regarded passenger trains as something they would like never to see again. So, for the 900 miles to Grandma's for Christmas, with lots of luggage, presents, camera equipment, and on and on, and the desire for a car when get there, the cost was really just the direct marginal operating cost, so I and nearly everyone else with a car took their car. E.g., when I drove that 900 miles, it was less than five miles from my apartment to an Interstate highway, and then I was on Interstate highways or similar for all but the last 15 miles where the traffic was very light and the roads fine. Yes, people have thought of the idea of having a car drive onto a special car of a train and then let the train do the driving while the people sat in the car, listened to the radio, now watched a movie on a laptop with a DVD, talked, etc. Didn't work -- not enough people came. Since the 1950s, the US has had a love affair with cars. Europe and the US have some significant differences. Actually, for shorter distances, there are good intercity bus lines in the US. Typically can get to/from a smaller city easier on bus than train or plane. As I recall, all of Germany is smaller than just the smaller US state of Oregon. There are a lot of places in the world where distances are large and population density low; we will see what they do about passenger transportation -- Mongolia, Siberia, Alaska, most of Africa, most of Canada, most of South America, much of South Asia around, say, Afghanistan, etc.