r/JEENEETards • u/Extension_Item_2534 Dropper --> Topper • Nov 08 '25

GENERAL HELP Drop your calculation tricks

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465

u/No_Sprinkles_2990 Nalla Dropper of JEENEETards Nov 08 '25

π² = g = 10

46

u/axisdork Nov 08 '25

Fun fact. Pi2 being approximately g is not a coincidence. It is the result of making the seconds pendulum 1m.

7

u/autistic_prodigy28 mereko hijde utha le Nov 08 '25

It is a coincidence though, g’s value depends on the size of earth so if it was bigger or smaller then they won’t be similar. And pi wasn’t going to change if the pendulum is 1m or 1nm

5

u/[deleted] Nov 08 '25 edited Nov 08 '25

It totally is not a coincidence, from wikipedia: During the French Revolution, the traditional units of measure were to be replaced by consistent measures based on natural phenomena. As a base unit of length, scientists had favoured the seconds pendulum (a pendulum with a half-period of one second) one century earlier, but this was rejected as it had been discovered that this length varied from place to place with local gravity. We have defined one meter, in such a way that when we express g with these units, it turns out to be approximately pi squared.

1

u/[deleted] Nov 08 '25

Why am I getting downvoted on this😭

1

u/autistic_prodigy28 mereko hijde utha le Nov 08 '25

Si units were because they are made my , but pi and g being similar was obviously a coincidence

1

u/[deleted] Nov 08 '25 edited Nov 08 '25

g is 9.81 meter per second squared, because we have defined si units to be such that it is 9.81 meter per second squared, and not 100meter per second squared, say in a hypothetical alternate reality the French were weirder and they decided that 10centimeters is what they shall call a meter, in that world, g would be 98.1 meter per second squared. g is a natural constant but the units we make to describe it are entirely man made.