Submitted by chrisdh79 t3_yd3b4e in Futurology
saberline152 t1_ittqp91 wrote
Reply to comment by ccooffee in Recycling plastic is practically impossible — and the problem is getting worse by chrisdh79
well depends on the fuel eh
cornerblockakl t1_ittrtax wrote
No. The kind of fuel doesn’t matter. It requires exactly the same amount of energy (fuel) to move 1 gram 1 meter (all other variables remain the same) regardless of the energy source. Jesus Christ, stop with the idiocy.
GubmintTroll t1_ittxyhx wrote
I think the comment of “depends on the fuel” is in reference to the comment of burning more fuel being an “environmental problem” and could be interpreted as meaning that the kind of fuel dictates the severity of the environmental problem. Not quite idiocy from where I stand.
whooyeah t1_itucuwk wrote
But if the fuel is burning in the sun then it’s Ok
Automatic-Leave-7258 t1_itu9hov wrote
That’s… not how energy works at all.
Moving 1 gram 1 meter can cost energy if you move the 1 gram to a higher potential, be energy neutral if the two endpoints are at the same potential, or even generate energy if you move the 1 gram to a lower potential.
The method you use to get it there can be more or less efficient, and it is almost always energy negative in practice due to friction… but what matters isn’t the mass being moved, it’s the integral of the force applied with respect to the distance traveled. That’s the definition of “work.”
The cool thing is that by this definition, you spend energy to accelerate a mass in the beginning, but as you slow the mass down to approach its destination, you can recover almost all of that energy as you apply a negative force to decelerate.
In fact, this is what the alternator in your car does. As you brake, the alternator recaptures energy used to accelerate the wheels, and it stores that energy in the battery.
cornerblockakl t1_itv7t2w wrote
That’s why I said “all other variable being equal.” Holy Christ.
Automatic-Leave-7258 t1_itvqhm5 wrote
I’m just saying moving a mass on a flat plane doesn’t use energy unless you really care about friction.
cornerblockakl t1_itw5ph1 wrote
Just. Stop. Talking.
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