measurements relating to the performance of different Mitzvot

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104 views

How big can a mezuzah be?

I read in the news about an Israeli designer, Yaakov Merdinger, who created the world's largest mezuzah case. As you can see in the photo, the mezuzah case is bigger than the door. Is this kosher? ...
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1answer
28 views

How far does one have to go into the ocean to say HaGomel?

When one goes "into" the sea, one is obligated to say HaGomel (see Berachos 54). How far does one have to go to be considered "in" the sea? If one goes swimming on the beach, does one say HaGomel? ...
9
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1answer
210 views

What is the hallachic definition of randomness?

A new Shabbat-friendly technology, KosherSwitch, uses randomly timed light pulses to create various safeks, so that flipping the switch does not hallachically count as switching the light on, even in ...
3
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2answers
100 views

How long does entire process of baking matzo take to be kosher?

If one would like to bake matzo or use flour to make a Passover food, how long do we have for the process to take place? If 18 min, then is that 18m59s or 18m00s? If the food is cooked before 18 ...
7
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1answer
152 views

Is ice considered food or drink in Halacha?

Is ice considered food or drink in Halacha? So for example, if one would eat an kezais of ice on yom Kippur, but it would not be equal to a reviyis, would he be liable for a chatas?
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1answer
35 views

Is there a concise book on how math and measurements are used in Torah and talmud?

Both the Torah and Gemarrah use math in various places, e.g. percentages (5ths (certain penalties); 10ths (ma'aser), etc.) They also use many terms of measurements - e.g. shekel = 20 gerah; numerous ...
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0answers
45 views

Can you carry an object from the step outside your house inside your house?

According to the laws of carrying on shabbos one may not carry from one domain to another aside from a makom petur ("exempt area"). A makom petur is less that 4X4 handbreadths and more than three ...
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1answer
77 views

Regarding chametz, what is considered “not fit to be eaten by a dog”?

Regarding whether something needs to be considered chametz or not, there is a general rule of ראוי לאכילת כלב - i.e. - if a dog wouldn't eat it, then it's not considered food and therefore it is not ...
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74 views

Would halachic units be shrunk if a person was (Honey, I Shrunk the Kids-style)?

In the classic move Honey, I Shrunk the Kids and its sequels, people get shrunk down to 1/264th of their normal size. So, a person is around 1/4 of an inch tall. If such a thing were even possible, ...
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2answers
77 views

What Bracha acharona on .5 kezayit of grapes eaten together with .5 kezayit of mezonot crackers?

What Bracha acharona on .5 kezayit of grapes eaten together with .5 kezayit of mezonot crackers? Do you say al hamichya ve'al haetz or is it boreh nefashot since neither is a kezayit? Please provide ...
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68 views

What is the the amount a person who feels weak on a fast day could eat or drink?

What is the the amount a person who feels weak on a fast day could eat or drink. How many ounces and how often?
2
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1answer
92 views

(Tefach) Wide Gartel

Some use a very wide gartel. A friend of mine mentioned an inyan (Judaism-sourced idea) that the gartel should be wider than one tefach. Can someone source this inyan that the gartel should be (more ...
6
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1answer
39 views

Menorah 20 Amos above ground level

One does not fulfill his or her obligation of lighting the menorah if it is 20 Amos above since it is not easily seen. The Rambam in Hilchos Shabbas 17:15 writes that a beam over a mavoi with ...
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1answer
48 views

Do brachos on seeing have to be made within four amos?

Is there any source that says that in order to make a bracha for seeing e.g., a sage of Israel, a sage of the nations, or an unusual animal, one must be within four amos of the person/thing? I found ...
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2answers
78 views

What was the volume of oil for one day's lighting of the Menorah?

Large jars for storing oil or wine were common in Judah. For 100’s of years, oil and wine were the commodities that were used to pay tribute and taxes. Many storage jars were standardized and may ...
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42 views

How big can a chanukia get?

I recently saw this story about students at YU who lit up their dorm windows to turn the entire building into a giant chanukia (just the form, not a real one). That inspired a question: Exactly how ...
3
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1answer
77 views

What is the shiur Hanaah?

How much Hanaah (physical benefit) must one have of things prohibited as an Issur Hanaah (things forbidden for benefit) like milk and meat, Kiley HaKerem (certain grape mixtures), or Avoda Zara ...
4
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2answers
90 views

What did they do for shiurim before modern measurements?

In recent centuries, authorities such as the Chazon Ish, Rabbi Chaim Na'eh, and Rabbi Moshe Feinstein ruled on the exact size of a tefach, ammah, kezayit, and other shiurim. What did people do before ...
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59 views

Has there been a discussion of changing the maximum height in halacha?

In halacha certain things are considered invalid because the exceed the maximum height which people will notice, 20 amos (menorah, sukkah, korah). In modern times many (most?) people live in areas ...
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0answers
39 views

What's the definition of “not now” for priority-of-b'racha purposes?

Orach Chayim 211 is about what food to recite a blessing over (that is, and eat) first when one wishes to eat two foods. It's clear that (except according to the Rambam cited in 211:2) one does not ...
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2answers
104 views

Measurements for the Bais HaMikdash — can we do it with a computer?

Since everything is computerized now, when the Bais HaMikdash is rebuilt, will we use the computer to rebuild? I.E., the measurements for the offerings, the entire rebuilding, etc.?
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3answers
1k views

Is there a “5 second rule” for foods becoming non-Kosher?

OK so I don't actually mean a 5 second rule. But is there an amount of time that it takes for something hot that comes in contact with a non-Kosher utensil or surface to become not kosher? For ...
2
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1answer
22 views

How much invalid material invalidates schach?

How much invalid material invalidates schach? (tefachim + inches preferred, but not required) Would it make a difference if this material was in the middle of the roof, or on the side (=next to the ...
5
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1answer
94 views

How much of a gap in schach is acceptable?

How large of a gap is allowed in a sukkah's schach (roof) without invalidating it? (in tefachim and inches/feet, if possible) Would it make a difference if the gap was in the middle of the roof, or ...
2
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1answer
71 views

L'Hafrish Challah with Dough Made by Multiple Women?

I am wondering if small portions of dough, made by separate women in a challah baking class (thus each small portion would be owned by a single woman), can be combined to create the requisite amount ...
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45 views

Must the entire decoration be within 4 t'fachim of the schach?

Inspired by Can too many decorations render a sukkah invalid? If there is a big decoration hanging from the schach, is it OK as long as the top (part, or most of the decoration) is within 4 tefachim, ...
4
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2answers
74 views

How far does dofen akuma stretch?

After reading Is a covered sukkah wall counted as a wall? i had a followup question on the answer there. (I was actually going to ask that, and had even drawn up diagrams, only to find that it was ...
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1answer
52 views

How much produce becomes bikkurim (first fruits)?

How much produce becomes bikkurim (first fruits)? Rambam says: Hilchos Bikkurim Chap 2 Halacha 19 How should one separate the first fruits? A person descends to his field, sees a fig tree, a ...
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1answer
79 views

Washing Once or Twice

Someone told me that technically one needs to pour water on each hand only once since we use large quantities of water. Is there a halachic source for this? I heard that the requirement to pour twice ...
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1answer
111 views

The Chofetz Chaim's kiddush cup

I read somewhere (don't remember where) that the Chofetz Chaim used a kiddush cup that was a smaller shiur than he recommends to use in his Mishna Berurah. Can anyone verify this and/or explain the ...
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1answer
71 views

What beracha acharona when ikar less than kezayit?

If you have an ikar (main) and tofel (secondary) mixture where the ikar is less than a kizayit but the entire mixture is greater than a kizayit, do you still make a beracha acharona on the ikar? Or ...
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0answers
27 views

Source for dying upon reaching a set number of words spoken [duplicate]

If I recall correctly, it says somewhere that we each have a predefined number of words to speak, after which we die. (The idea being that one should be careful not to speak unnecessarily.) Assuming ...
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54 views

How much Matzo must one eat on Pesach?

According to the OU, one must eat a minimum of "approximately 26 cubic centimeters" of Matza and Marror to fulfill his requirement (ie, a kezayis is 26 cm3). They also provide a chart, which states ...
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2answers
74 views

Where does the contemporary measurement of a Kezayit come from?

According to the Nodeh B'Yehuda and the Chazon Ish, in order to calculate the size of a kezayis (which apparently is based on the size of an egg), we must double the size of our contemporary eggs. ...
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0answers
48 views

the measurements of Noah's arc and the arc of the covenent

The volume of Noah's Ark is 450,000 cubic cubits. The volume of the Ark of the Covenant is 5.625. Noah's Ark was thus exactly 80,000 times larger than the Ark of the Covenant. Is it significant that ...
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1answer
288 views

How many Oreos in a kezayis?

For standard Oreo cookies, how many would be a kezayis by volume? I have heard maybe 2.5 or maybe 3.
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1answer
95 views

How does one do Hagalah above 12,000 feet?

How does one do Hagalah above 12,000 feet, where water's boiling point falls below 190°F? Under normal circumstances, the water will not be Rochsim, and therefore unsuitable for Hagalah. Using a ...
3
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1answer
119 views

Soldier's Shovel

Is there a shiur for the item the soldier is obligated to carry in Devarim 23:14? וְיָתֵד תִּהְיֶה לְךָ עַל אֲזֵנֶךָ וְהָיָה בְּשִׁבְתְּךָ חוּץ וְחָפַרְתָּה בָהּ וְשַׁבְתָּ וְכִסִּיתָ אֶת צֵאָתֶךָ ...
4
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2answers
122 views

Kaddish yatom: what if a parent really *is* wicked?

I understand that a soul may be judged for a full 12 months after death but that we (generally) only say kaddish yatom for a parent for 11 months because the longest period is for the worst sinners ...
5
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3answers
165 views

Why are we required to light Chanukah lights only for about half an hour?

Since the miracle of the oil of Chanukah was that from one flask of oil they miraculously had enough oil for the menorah to burn all night for eight days, why did Chazal require us to light only for ...
5
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2answers
99 views

challah bracha on separate dough balls

I understand a bracha on dough is made if the amount of flour is greater than a certain amount, sourced here. I have a small food processor I use to knead the dough. I plan to make a bunch of dough ...
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0answers
88 views

How is a ten tefachim wall hard to use?

The Gemara in Eiruvin 77a says that when a ten tefachim wall is between two courtyards, but is less than that to one courtyard (the floor of the courtyard is heigher), we give it to the one which is ...
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1answer
121 views

how much water do you need for a Netilat Yadayim

When washing your hands for Netilat Yadayim, how much water do you need for Netilat Yadayim?
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1answer
104 views

Shiur for kiddush rabba mezonos

When we make kiddush rabba with mezonos before having a real meal with bread, is there a shiur for how much mezonos a person should eat in order for it to be yotzei kiddush? Does it matter whether the ...
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57 views

3 Pesukim minimum per Aliyah

Why is it that each aliyah for Krias Hatorah has to be 3 pesukim at minimum? I know that the minimum for an entire krias Hatorah on a weekday is 10 pesukim (with the exception of Purim being 9 ...
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1answer
125 views

How long does it take to become a kofer?

If a person for whatever reason momentarily has a thought which denies God, but then afterwards reaffirms his belief in Hashem, is that an act of kefira? Does a momentary lapse in belief constitute a ...
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1answer
324 views

Which shita are those wearing extra long tallit katan following?

Some rabbonim are wearing really long and large talith katan. For example Rav Shmuel Auerbach shlita (picture below). Rav Elyashiv ztl used to wear a very long one too. Which shita are they ...
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1answer
67 views

Is there a legal minimum on the amount of soil needed to make a suitable grave?

This is not being asked for any pragmatic need. I had the thought about people living off of planets. Without getting into the issue of whether a burial can take place anywhere beside Earth, I ...
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1answer
36 views

Is there a concept of giving a fatter sacrifice?

Is there a concept of giving a fatter sacrifice as opposed to a smaller one? I believe the Torah says there are different levels of sacrifices depending on your wealth (e.g. a cow vs. a bird vs. ...
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1answer
303 views

Which is the height considered 3 tefachim for not “praying in height”? (30cm?)

Recently we had to make a synagogue for one day at a hall, and we used a scaffold for the Shaliach tzibbur to be well heard by all the public. The Scaffold was 1m x 1.5m, and I don't remember the ...