Mechanical Engineering

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Posting here hoping for a physics-based reply.

I viewed a vid re power versus torque in vehicles. My understanding is that power is torque multiplied by angular velocity. Given an amount of power, a high-torque vehicle won't go very fast. A very fast vehicle won't tow a very massive load.

I related it to my little knowledge re stick shift. Gear 1 is used to move a stopped vehicle or for low speeds. Does gear 1 mean max torque and lowest angular velocity? I imagine you need a high torque to overcome static friction. Does gear 2 mean a dip in torque and a rise in angular velocity? Does the max gear mean lowest torque and max angular velocity? When I was young, a driver said one can carefully switch from gear 1 to 2 then 2 to 3 (and so on) on a wide road with very few surrounding vehicles. He said this was the way to increase the velocity and a high gear generally meant more fuel-efficient.

Please correct me if any of the above is wrong.

I googled. Here's what I read –

" 'Revolutions per minute' is how many revolutions the engine itself is making per minute. The gear ratios then translate revolutions of the engine into revolutions of your tires (more or less). Lower gear means lower tire revolutions per engine revolution, but also the tires are easier to turn.

"So when the car is going slower, meaning it requires more force to accelerate, you want lower gears. As the car speeds up, you need less force to go faster or maintain that speed, so you switch to a higher gear, sacrificing power for more efficient use of your engine."

I didn't ask an llm to avoid hallucinations.

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Wanted to ask about this. I do not work in California, however many of our vendors and customers are seeking to swap to MIL-PRF-8625 Type II, when they historically used Type I.

I'm totally on board with this - anything I can do to push safer, less environmentally destructive processes is a win in my book. But I understand that not all companies are interested in jumping ship so fast.

So I wanted to ask, what's your companies take on it? Did you know about the industry phase out?

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The US Space Force is tracking 20 pieces of debris from the Intelsat 33e.

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I've been dealing with this for months. I've received yet another drawing from a company calling "Diameters on a common axis/center to be 0.XX" TIR U.O.I. "

Total Runout requires a Datum. Your "common axis" is not a datum and can not referenced. It's driving me mad. Like, where did everyone get this notion that it's acceptable? It'd be one thing if it was just one or two drawings, but I'm into the dozens at this point. It's getting to the point that I'm starting to question if I'm either the one in the wrong or everyone has some sort of mass psychosis.

Am I in the wrong here?

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Scientists and engineers have successfully tested a high-powered laser weapon mounted on a British Army combat vehicle.

According to the Defence Science and Technology Laboratory (Dstl) and the Ministry of Defence (MOD), this trial marks the first instance of such a weapon being fired from a UK land vehicle.

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What aspect are you most passionate about and why ?

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Hey folks, I'm working on a project involving the design of a heat exchanger, and I've hit a bit of a wall. I'm trying to optimize the fin design for maximum thermal efficiency while keeping the pressure drop within acceptable limits. I know the general principles, but I'm struggling with the specifics of selecting the right fin geometry and material.

Any tips or resources you could recommend for tackling this?

Appreciate any advice from those who've been down this road before!

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Crosspost from the "Energy" Community. Seemed too good not to put here.

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Is there any mechanical engineers? What you would wish to know when you were starting learning? What skills and topics you consider the most useful in mechanical engineering?

What is the fastest way to learn mechanical engineering in the nowadays when 3d printers are avaliable to be able to design and make custom clocks, engines, generators?

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Just build a replacement nuclear power plant and reuse the water. Right?

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I can't stand the SpaceMouse Pro. They ruined it! Why would they swap the nice tactile buttons for stupid gummy membrane buttons? And why coat the whole thing in nasty soft touch coating that is going to turn to goo? We peaked with the previous generation of space balls.

Since I've been working from home though, it has gotten quite annoying to unplug my SpaceExplorer and take it back and forth to the office. It would be so nice to have one of those fancy new wireless ones. But that's not happening, since they ruined it.

So, I added USB-C to mine, instead. Now, I'll just have a cable at the office, and a cable at home and just take the unit itself back and forth. I can even leave a USB-C to USB-C cord in my case, in case I need to use it with my laptop away from my docks! If anyone is interested, I can share the STL for the little breakout board mounting piece I made.

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A University of Virginia professor believes he has discovered how to create a freeze-ray device, inspired by the Batman villain, Mr. Freeze. Rather than being a weapon, this device is intended to cool down electronics within spacecraft and high-altitude jets.

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