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2d
comment Push a Boeing 737 on ice: Did this guy have a chance?
@MooingDuck: That is because I ask if the worker can prevent the plane from sliding further, i.e. when it stops between slides. In the beginning of the video, it can be seen that the plane slides a bit, then stops, before it starts to slide again.
2d
comment Push a Boeing 737 on ice: Did this guy have a chance?
Actually, the nosewheel does seem to be a bit further from the main gear than is the center of area of the vertical stabilizer.
2d
comment Push a Boeing 737 on ice: Did this guy have a chance?
Terrific analysis, thank you! I'm happy to see that the little blue jacket man, had he been equipped and knowledgeable, actually stood a chance after all!
Aug
19
comment Am I attracting Pluto?
This is a beautiful, well thought-out answer. It's answers like this that keep me on Physics.SE.
Aug
17
comment Am I attracting Pluto?
Unless you are Alan Stern, I stand by the assertion that Pluto is not affected by the fact that you are alive in any way!
Aug
13
comment Halley's Comet as a “Free Taxi”
@ericksonla: I believe that the word you are looking for is "lithobraking".
Aug
11
comment Is a bomb's shockwave strong enough to kill?
In 2006 in Lebanon a mortar landed just about a meter or two away from me. I was wearing a helmet, combat vest, and very light (shrapnel) armor at the time. There was no shrapnel from the (possibly improvised) mortar, but the blast blew me back into the wall behind me and I was out for a few seconds. I'm still here to tell about it!
Jul
1
comment How to emulate 40ft (12 m) of water?
By far the safest and easiest to implement solution. Any leaks or other issues that the OP will have with this method, he would have with any of the other methods as well.
Jun
8
comment Why do two flames kept side by side merge into a single flame?
Very nice answer for a relatively new P.SE member. Thank you!
May
27
comment Why do electric sparks appear blue/purple?
Note that the answers below also apply to lightning.
May
19
comment Does a well-lit mirror weigh more than an unlit mirror?
Most of the effect of the light on the mirror will be on the non-reflective side, such as heating it up.
Apr
29
comment Does a truck stop faster if the stack on the back of truck is stable or if it moves forward?
@WetSavannaAnimalakaRodVance: You guys have semitrailers with an odd number of wheels? Or is the steering wheel counted in there too?
Mar
19
comment Could we send a man safely to the Moon in a rocket without knowledge of general relativity?
I suppose that special relativity would counter a portion of the difference, my guess would be about 10-20%, considering the TLI speed of over 10 km/sec.
Mar
2
comment Why doesn't NASA use RAMJET rockets to get into space?
Related discussion on Space.SE
Mar
2
comment Why doesn't a cigarette lighter generate thrust?
@lemon: Did you cause this mess?
Feb
5
comment Why do most formulas in physics have integer and rational exponents?
This answer hits the nail on the head at the beginning: the reason is that the relationships in question are all linear. Why are they linear relationships? For the geometrical measurements, the answer is proportional scale. For the physical measurements, the answer is (usually) conservation of energy.
Dec
31
comment Does a ball resting on the ground have acceleration?
@WetSavannaAnimalakaRodVance: Thank you for clarifying the meaning, via the etymology, of the term "proper". That makes understanding some concepts so much easier!
Dec
19
comment Why isn't length contraction permanent even though time dilation is?
The length of space passed is in fact permanently contracted. Without loss of generality, consider a particle moving at C. For it the space passed contracted to 0 and the time passed was 0. If the space travelled were not permanently contracted, the particle would not be permanently at the new location after 0 time. Note that this does not imply that the distance can be traversed again in its contracted state.
Dec
13
comment Is a block of cotton heavier than a block of iron?
@Hypnosifl: Answer edited to address your comment. Thank you.
Dec
2
comment Cooling a satellite
@HotLicks: EVA suits sublimate ice into vapor as a cooling method. I do believe that the vapor is recovered, though I'm not sure. A recent mishap with that system had water collecting inside a space suit, sending the astronaut rushing back to the ISS airlock.