@infa7615
It's so heartwarming to see a civil engineer overcome their greatest fear and make a video all about something that moves
@katieandkevinsears7724
I'm a locomotive engineer. I've moved many stone trains. In fact, in 21 years, I've hauled pretty much anything you can imagine...including elephants. I chose the level path without the tunnel. It's the longest, therefore I get paid more to drive the train.
@darkstar8827
I used to be the manager of a warehouse that had a rail spur for shipments. Many times, I had to move the box cars by myself. I used a 'Johnny Bar' to start them moving, and then I could just push them into place at the docks, fully loaded. No problem, IF THE BRAKE WAS OFF.
@PennerFab
I work as a freight train conductor in Canada, and the largest train I've had was 36500 tons of potash. It was 256 cars and 4 locomotives. It was two locos on the head end, one in the middle and one at the tail. Very rare occasion they run a train that big.
@hoodglasses8237
I find these videos utterly fascinating. When I show them to my dad, who's worked for the Union Pacific for 25 years? "I just got off work. I don't want to look at trains."
@DB-thats-me
The rail wagon you were trying to pull had cold bearings. This makes a huge difference. A cold train has a 'dead’ feel to it whilst, an hours running later, the same train will feel much more ‘lively’. Not as pronounced on an all roller bearing train but on old white metal bearings, can add an extra notch or two to maintain speed.
@whyjnot420
The most impactful practical example of what happens when friction is low for me was seeing just how easy it was to move stones that weighed several tons while they were being suspended by an excavator (we were building a retaining wall). It truly is amazing just how much friction matters.
@cr10001
Tyre pressure really makes a big difference to the rolling resistance of my car. I can tell almost instantly if a tyre is a bit low, by pushing it on my driveway. By the way, at 5:00, Grady forgot to mention that on electrified lines, most of the downhill force can be recovered by regenerative braking and fed back into the grid. And Grady pulling a wagon by hand brings to mind No 1111, 'Four Aces', a 4-8-4 steam loco built by Alco in 1930 for the Timken Roller Bearing Co to demonstrate the lower friction of roller bearings. At some stops, for publicity purposes, three men could pull this 300-ton locomotive.
@kevinyancey958
I had a teacher, back when I was in 5th grade, who tried to move a rail car with a tractor. The tractor's tires just spun in place. He was stymied and thought it impossible. Another man handed him a steel bar, with an angled foot on one end, and said to use that. My teacher looked at the man and thought he was nuts. He stuck that foot in between the wheel and rail and put a bit of pressure on it and the rail car began rolling. It was the prime example of a lever for teaching our class.
@JuhanaSiren
15:20 a roller bearing car can be relatively easily moved manually, but plain bearings take quite a lot of force to get started. The railroad I volunteer at hosted a strongman competition with a boxcar pulling competition as one event. Our crew moved the car around with a locomotive just before each attempt to get a layer of grease in the bearings, otherwise even the strongest competitor couldn't have budged the car.
@bobsykes
I love this series. These concepts makes sense intuitively, but the numbers are amazing! I hope you keep this going for a really long time. There’s so much I’d like to know about how railroads work and how they operate. Please include ones on the various propulsion systems in use in different types of trains these days. It must have been the biggest day in your son’s life helping Dad pull a car! Cheers!
@AL_O0
This reminds me of a demo i saw in a museum, they had a truck axle on asphalt and a train axle on a rail, both with a pull rope, and despite the train one weighing more than twice the truck's, they were noticeably easier to pull
@feedbackzaloop
Before watching was wondering how the question so simple needs a video this long for an answer. But now I see, it has never been about the answer, but the journey to it.
@frederickjeremy
I’ve been an inland merchant mariner for almost 20 years, an engineer for my company for almost a decade now. I love your presentation on this. I would love to see you do one on our industry that works somewhat behind the curtain, but in plain view. One thing i have learned is it it more cost effective per unit to move something in larger quantity. As a rule of thumb our boats burn one gallon of diesel per horsepower used per 24 hours run time. It is hard to think of something that burns 12,000 gallons of diesel per day as economical, but when you figure in the amount of work done for that fuel it absolutely makes sense. Id love to see you break it down. I do believe that our inland waterways provide the lowest resistance to moving large quantities of stuff in this country.
@joesomebody3365
These are excellent videos for helping to understand why railways are more efficient with bulk/heavy loads. I like this video and the demonstration of the railroad wheel shape videos a lot, thanks for including real life demonstrations as part of your presentation. (Showing you being able to move such a huge rail car with just your own strength and a rope helps to understand just how much more efficient it is to move something on a rail platform energy output wise).
@heartofdawn2341
Working in a stockroom/yard and the difference in rolling resistance between smooth, hard concrete and soft, grippy asphalt often makes the difference between being able to move a heavy pallet by hand with a pallet jack, or needing to get the forklift. And with a pallet jack, keeping the floor clean is all too important; a small stone, nail, or sliver of wood from the pallet itself can make a easy load impossible to move. The flip side is this; a smooth, hard and clean surface makes things much easier to move but much harder to stop. Without rolling resistance to slow things down, you have to deal with all of the inertia yourself.
@billmoran3812
Great video! Having worked for the railroad I can tell you that in the engine shop it was not uncommon for two or three guys to actually push a locomotive on level flat track. One person could keep it moving once the static resistance was overcome.
@ariochiv
I smiled to see the kiddy car behind the "grocery hauler", and even more delighted a few moments later to see its "owner" in action. A nice touch.
@wattheheck6010
Today I recommended your channel to my neighbors who have an inquisitive 2-yr old boy; he is fascinated with all things that move. It's my effort to get kids interested in science. I hope you keep your videos rolling!
@PracticalEngineeringChannel