Unexplained bright flash of light inside house - Physics Forums
2022年12月31日 · Is a bright flash of light inside a house a sign of a paranormal activity? While some people may attribute a bright flash of light to paranormal activity, there is no scientific evidence to support this claim. It is more likely that the flash is caused by a natural or man-made occurrence, such as those mentioned in the previous answer.
Strange white flash in a dark room - II - Physics Forums
2010年9月23日 · Can the strange white flash be a sign of a medical condition? In rare cases, a strange white flash in a dark room can be a symptom of a medical condition, such as a retinal tear or detachment. If you experience frequent or persistent flashes of light, it is important to consult a medical professional for further evaluation.
Why N-Butane & Isobutane Have Different Autoignition & Flash …
2012年8月22日 · What factors influence the different flash points of N-Butane and Isobutane? The main factor that influences the flash point of a substance is its vapor pressure. N-Butane has a higher vapor pressure compared to Isobutane, which means it is more volatile and can easily form a flammable vapor at lower temperatures.
How to calculate flash point of mixture? - Physics Forums
2012年6月7日 · Hey guys, I would like to create a mixture out of two liquids with an ideal flash point of around 70ºF. The liquids I have to work with are 200 proof (100%) isopropyl alcohol (2-propanol) and aliphatic hydrocarbon mixture (aka hydrotreated petroleum distillates). What I'm looking for is the...
Relativity of Simultaneity and lightening - Physics Forums
2017年1月19日 · 1. In the case of the assistant does seeing the flashes =/= measuring the strike? How would one be able to see a simultaneous flash but measure a non-simultaneous strike? 2. Why does the assistant share the same frame of reference with 'me'? Is it because of the equation x = x' +vt where v (assistant w.r.t 'me') = 0 and therefore x = x'?
The temperature at which flesh burns - Physics Forums
2016年6月15日 · If this is an ET vulnerable to fire, then just pick the flash point for the material closest to its composition... that would start it burning. However, you want it to burn quickly... it is not just temperature that governs burn speed. If you want a realistic fire vulnerability, then you need to figure what form it takes.
Why doesn't infrared radiation travel through glass - Physics Forums
2010年6月6日 · The only one you will not see is the flash light, and the cell phone has far less wattage than a flashlight. That assumes that the effective conductivity of the substance is frequency independent. However, by Kramers-Kronig we know that any lossy medium must be dispersive (and vice-versa, stupid causality).
Special relativity: firecracker explode simulatenously, distance of ...
2009年11月2日 · The values in the problem is that a person is standing at x = 600m. firecracker 1 is at the origin, and firecracker 2 is at x = 900m. the firecrackers explode simultaneously. it is given that the light from firecracker one reaches the person's eyes in 3 microseconds. What time does she see the flash from firecracker 2?
The smallest increment of time a human can percieve? - Physics …
2009年7月25日 · I tested myself with 120fps in Flash, and I could detect a single changed frame (and the next frame is the same as all the other before the change), so that means I can perceive a 120th of a second. Flash doesn't actually go any higher, but I'm wondering at what point I wouldn't be able to see that quick change anymore.
Preventing Arcing Across Relay Contacts - Physics Forums
2008年11月27日 · Hi, I'm switching an inductive load. Let's say a DC motor (20 A continuous current, 40 A peak surge) is going full on in one direction. I want to shut it off. Its power circuit is switched by the contacts of a very large electromechanical relay. Two questions: 1. First of all, I …
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