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Anons are physicists (imgur.com)

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[–]jmlinden7 [スコア非表示]  (13子コメント)

It's 0, work done is equal to kinetic energy added. The car is at the same speed at the end, so its kinetic energy hasn't changed

[–]Jahzmzna83f2 [スコア非表示]  (12子コメント)

Of course, that's why if I take a box on the floor and lift it above my head, I've done no work, since the box is stationary in both states. Oops it seems I've stumbled upon a way to make infinite energy. Where's my Nobel Prize?

[–]murIoc/pol/ack [スコア非表示]  (11子コメント)

ok sperglord, i don't know how anyone could be this retarded, but ill bite. when you lift the box above your head both you and gravity are doing work on it (opposite directions), so if the box becomes stationary afterwards the net work is 0.

kill yourself

[–]Jahzmzna83f2 [スコア非表示]  (10子コメント)

If every force has an equal and opposite force (Newton's Third Law) then the net work for everything is 0 everywhere, and the term "work" has no meaning.

kill yourself

[–]murIoc/pol/ack [スコア非表示]  (7子コメント)

no. people don't define work on "everything", they define work on a specific system. if there's a car that starts at rest and accelerates to 20 mph, it has done nonzero work. no one cares about something outside your system (the road, the bird on the tree, you sucking a guy off in an alley) because that's not what your measuring.

[–]Jahzmzna83f2 [スコア非表示]  (6子コメント)

I was mocking your explanation because you included gravity as part of your system, which any reasonable person would not do.

[–]murIoc/pol/ack [スコア非表示]  (5子コメント)

why wouldn't you include gravity? it's acting on your system so you have to account for it. what you want to say is that the PERSON is doing nonzero work on the box, not the box has non-zero work being done ON it

[–]Jahzmzna83f2 [スコア非表示]  (4子コメント)

that's the whole point of all of this. The problem is so mired in rhetoric and terms are so undefined that you can argue for days about some shitty high-school physics problem. I'm gonna go back to work calculating NPSH values for my plant turbines...

[–]GeesusChrist [スコア非表示]  (2子コメント)

calculating NPSH values for my plant turbines

implying that calculating net positive suction head isn't something that any autist with a 30 cent app and a grade 6 education couldn't do

I bet you have the word engineer in your title and feel all important and shit. Go mop a floor. Your fancy acronyms are useless in impressing actual engineers with degrees.

[–]Jahzmzna83f2 [スコア非表示]  (1子コメント)

I'm actually an autist with a grade 7 education, and the turbines are to quickly pump up my warehouse full of inflatable waifus

[–]manset/mu/tant [スコア非表示]  (0子コメント)

plant turbines

GROWING POT FBI FBI FBI FBI FBI

[–]canarack [スコア非表示]  (1子コメント)

Work is done if a mass is accelerated/decelerated over a distance. That's all. We're not talking about how much energy the car would have to expend to maintain a constant speed, we're talking about work done.

[–]claudesoph/b/tard [スコア非表示]  (0子コメント)

Work is force exerted over distance in the same direction. Acceleration has no direct bearing on it.

http://en.wikipedia.org/wiki/Work_%28physics%29