## 613

Author: Miryam Alter Math Level: Prime Numbers Grade Level: middle school Topics: Prime numbers, square roots, factors, division The Question: ——————- Is 613 a prime number? The Answer: —————– Yes it is prime. You need only check odd numbers up...

## Space Under the Cart

In parsha Nasso (Bamidbar 7:3) the Nissim (tribal leaders) donated carts to carry the parts of the Mishkan.  The Gemara in Shabbos 98a discusses the definition of a public domain. The Gemara specifically addresses whether a roofed area can...

## Private Space

In parsha Beshalach (Shemos 16:29) it says that the Jewish people should not collect the mon on Shabbos. Some opinoins identify this is as the source for not carrying on Shabbos. This  prohibition incudes not carrying in a public area....

## Seeds of Torah

In Vayikra 19:19 we are given the commandment “not to plant your field with mixed seeds”. The Gemarah (Shabbos 84b) explains that seeds which are side by side need to have a three tefach distance between the rows. However, if...

## Twilight

In parsha Breishis (1:5) Hashem separated between day and night.  There is a time of the day called Bein Hashmashos.  This is a time which we are in doubt weather it is day or night. In Shabbos 34b the Gemara...

## Eyesight = a (1 – r) ^ x

The Gemara quotes a statement of our Sages that when a person takes a very large step he loses 1/500th of his eyesight.   Tosfos points out the issue that based on this a person who takes 500 large steps would...

## Meditation

We are told in parsha Eikev (Devarim 10:20) “Him you shall serve”.  This is the commandment that requires us to pray to Hashem. The Gemara sites a B’raisa that the pious would spend an hour in meditation before prayer, and...

## When’s Mincha?

We are told in parsha Eikev (Devarim 10:20) “Him you shall serve”.  This is the commandment that requires us to pray to Hashem. A standard hour (SH) that we normally use is 60 minutes long. A halachic hour (HH) is...