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age 36
visits member for 2 years, 8 months
seen 22 hours ago

Feb
19
comment Second law of Thermodynamics: Why is it only “almost” always true that entropy is non-decreasing?
Thank you. I will google Poincarè.
Feb
19
answered How can I calculate the amount of bubbles needed to lift a submerged body?
Feb
19
accepted Second law of Thermodynamics: Why is it only “almost” always true that entropy is non-decreasing?
Feb
19
asked Speed of a dynamic hydraulic system
Feb
15
comment Second law of Thermodynamics: Why is it only “almost” always true that entropy is non-decreasing?
@Anna: If the law pertains to classical thermodynamics however the "almost" pertains to statistical, then in my opinion the word "almost" should be removed as it refers to a different field. Why conflate the two?
Feb
15
asked Second law of Thermodynamics: Why is it only “almost” always true that entropy is non-decreasing?
Feb
11
accepted How are magnetic fields transmitted?
Feb
3
comment Is it safe to observe the sun through binoculars with welding glass in front?
Also note that almost all common welding masks are Shade 12 which is not sufficient. I personally would not use a welding mask, it is dangerous.
Feb
3
comment How are magnetic fields transmitted?
Thank you. I see that it is in fact nitty gritties that I need to grasp!
Feb
3
comment Does being suspended in air allow you to not be affected by Earth's rotation?
@Zassounotsukushi: You can have rocket thrust without an atmosphere, that is how most spacecraft manoeuvre in fact. In any case, it is not the atmosphere that Rennie is concerned with when he states that you are still moving sideways at the same speed so the spot you took off from remains below you. He is concerned with your initial sideways velocity, imparted upon you by the ground your were standing on before launch. Likewise, if you throw a ball out of a car window perpendicular to the car, the ball will move at an angle to the ground, its forward component equal to the speed of the car.
Feb
3
asked How are magnetic fields transmitted?
Feb
1
answered Finding Directions using moon
Feb
1
accepted How to describe the inner curve of a crescent?
Feb
1
comment How to describe the inner curve of a crescent?
Note that you have "eclipse" in place of "ellipse". I don't have edit privileges, but that might confuse some other readers.
Feb
1
comment How to describe the inner curve of a crescent?
Thank you Frank, it seems to me that you are correct. Once it is recognised that the terminator is described by an ellipse the pieces fall into place. Have a great day!
Jan
29
comment Effect of coarse vacuum on consumer electronics?
Contaminants in air may be more destructive than sublimation in a vacuum. Just the water vapour in air could corrode the components.
Jan
29
comment What would be the optimal weight of a ball if I want to throw it as far as possibile?
One could postulate that by saying "assuming a force X" the OP really meant "assuming initial energy of the ball as X", as most real-world systems for launching a ballistic projectile will have fixed energy.
Jan
29
accepted Is it possible that I just saw Jupiter's moons?
Jan
29
accepted Why are refrigerators 4 degrees and freezers -18 degrees?
Jan
29
awarded  Critic