hebrew - vowels on vav before mem

Can someone explain why the following examples, all from parashat ki tzetzeh - כִּי תֵצֵא, are written with a kamatz:

yet the following is written with a shuruk:

kanji - Difference between Japanese words for illusion with 幻

I was reading about the kanji 幻, which I take to mean illusion or vision(not 見 vision), and looked at words with it. I saw the words:

• [幻滅]{げんめつ｝-disilusion


• 幻想｛げんそう｝-illusion



• 幻覚｛げんかく｝-hallucination


• 幻影｛げんえい｝-phantom


• 幻｛まぼろし｝-illusion


• 夢幻｛むげん｝-fantasy/phantom

Is that the correct translation of the words? Are some more common than others? What are the different connotations of each word for an illusion? A lot of them, like 幻影 and 幻 look similar, but the first seems to be more of the ghost kind, but I'm not too sure. What's the difference between 錯覚 and 幻覚?

Answer

• 幻影【げんえい】 / 幻【まぼろし】: Almost the same, except that the former being 漢語 and the latter being 和語. Some ghostly or dreamy things that may or may not exist. 「幻の大陸」 means a continent whose existence is not confirmed.


• 幻想【げんそう】: This comes off to me as "imagination", "fantasy" or "fiction" rather than "illusion". It's in titles of many comics and games, but we usually don't use it in daily conversations.



• 夢幻【むげん】: This is another cool-sounding word for novelists and artists. As an otaku I recall I saw this word many times, but never sought for its definition. Usually "夢 and 幻" is enough to understand it.

And the following words are scientific terms, which are medically or psychologically defined. But you can safely use these in daily conversations, too.

• 幻覚【げんかく】: =Hallucination. To perceive something which is not really there, usually due to mental illness. It includes 幻視【げんし】 and 幻聴【げんちょう】, which are typical symptoms of schizophrenia.


• 錯覚【さっかく】: =Illusion. To perceive something which is really there, but in a distorted way, even when the sensory system is normal. The best-known is 錯視【さくし】 (optical illusion), aka 目の錯覚.

passover seder hagada - Source of the "remove his teeth" gematria

In the Hagadah (page 8 of here), there is a line by the wicked son that says you should "remove his teeth" (hakeih et shinav). A common explanation is that the gematria of "rasha" (reish shin ein: 570) minus "his teeth"(shin nun yud vav: 366) equals "tzadik"(tzadi daled yud kuf: 204). What is the earliest use of this gematria to explain that line?

sources mekorot - Jews were on 49th level of Tumah. Says who?

There is a well known idea that when the Jews left Egypt during the Exodus, they were on the "forty-ninth level of tumah". Many explanations are given for this and it is expounded upon at length by a number of great commentators and other writers.

However, whenever I've seen this concept brought up, it is always with a vague reference or none at all. I've seen it introduced with "...ידוע הוא" or "...אמרו חכמינו ז"ל" or "...נכתב בספרים הקדושים" or the like, without any direct quote as to where this comes from. A search on Bar Ilan doesn't find anything earlier than around the 17th century that talks about this idea; certainly not any midrashic sources.

Where does this concept come from? I'm looking for its earliest source, preferably a midrashic or Talmudic one.

Answer

I Googled it and came up with this page (see top left). It says to look at Zohar Chadash Yisro 31a.

In the Zohar, it is referred to as ארבעים ותשע חילי דמסאבותא

tobacco cig smoking - What are the sources of saying a beracha before a cigarette?

I've heard that before smoking a cigarette, Briskers make it a point to drink something shehakol and are mechaven the cigarette...

Why do they do this?

inorganic chemistry - Are there any sodium salts that are insoluble in water?

Are there any sodium salts (e.g. NaCl) that are insoluble in water? If so, what are their approximate $K_\mathrm{sp}$ values?

organic chemistry - why are amines more water soluble than alcohol for similiar molecular weight?

kindly someone please explain the reason behind this behaviour despite the fact that oxygen is more electronegative and forms stronger hydrogen bond.