Rabbi Baruch Bodenheim: Gemara Eruvin: First Perek, יום שני Elul 4, Daf 14a-14b (08/21/23)

Review the גמרא דף יד. “היתה של קש (two dots – second medium line) until the משנה דף יד עמוד ב

Question:

The Gemara is very exacting with the mathematical calculation of the ratio of the circumference of a circle to the diameter (3:1) taking into consideration the thickness of the walls of the basin.

How could this be when the real ratio of the circumference of a circle to the diameter is pi (3.14:1)?

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And תוספת יום טוב says since קורה is only required mdrabanan they are lenient even to consider the width of tefach even though it is a little narrower.

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Learn רש”ש who asks what about the opinion that lechi and Korah is a Halacha Lmoshe M’sinai?

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And חזון איש או”ח ס’ קלח אות ד

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Learn the משנה דף יד עמוד ב and the Gemara until “תנא עשה לחי

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Question: