Twitter proof: folding my way to the moon


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In this twitter proof we will see how the exponential function can mess up with objects from our daily lives!..

Claim: with less than $50$ folds, a piece of paper will be so thick that it will cover the distance from the Earth to the Moon.

Twitter proof: a common sheet of paper is $0.1$mm thick. If we fold it once, it becomes $0.2$mm thick. Folding twice, $0.4$mm. Folding $49$ times, the paper becomes $2^{49}\times 0.1$mm thick, which is around $5.63\times 10^{13} $mm or $5.63\times10^7$km, $141$ times the distance from the Earth to the Moon ($398818$km).
Neste post vamos ver como a função exponencial pode interagir com objetos do nosso quotidiano e criar resultados inesperados.

Proposição: com menos de $50$ dobras, uma folha de papel fica com uma grossura superior à distância da Terra à Lua.

Prova num tweet: uma folha de papel normal tem $0.1$mm de grossura. Se a dobrarmos uma vez, fica com $0.2$mm de grossura. Dobrando de novo, fica com $0.4$mm. Dobrando $49$ vezes, a folha fica com uma grossura de $2^{49}\times 0.1$mm, que dá aproximadamente $5.63\times 10^{13} $mm ou $5.63\times10^7$hm, $141$ vezes mais do que a distância entre a Terra e a Lua ($398818$km).

  - RGS

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