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HNQ
5:09 AM
2
Q: Can people feel the low heat radiation from very cold surfaces?

Ram RachumHere's a thought experiment about the way that heat is transferred through radiation. Humans can physically feel when a hot object radiates heat on them, such as a campfire or an infrared-based space heater. But can humans feel cold objects the same way? Say that a scientist is working in a resea...

2
Q: Equation of Motion Invariance in Galilean Mechanics

Andrei CosminConsider a particle moving freely, where $\vec{r}(t)$ is the position of the particle. Suppose I move into a frame with $$\vec{r}' =\vec{r} + \epsilon \vec{F}(\vec{r}, t)$$ , where $\epsilon$ is an infinitesimal variation and $\vec{F}(\vec{r}, t)$ is an arbitrary function (e.g. $\vec{F}(\vec{r}, ...

 
 
16 hours later…
HNQ
8:43 PM
4
Q: Is there proof for: "Elements heavier than iron will decay to iron by processes such as fission and alpha emission"?

Sourabh ChoudharyFreeman J. Dyson in his "Time without end: Physics and biology in an open universe", Lecture 2: Physics, part G: All matter decays to iron, claimed that on a long enough time scale "Elements heavier than iron will decay to iron by various processes such as fission and alpha emission". I'm not abl...

 

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