1. The problem statement, all variables and given/known data This is not homework, I'd like to know if it is possible to find the pitch a log spiral knowing that at every round (2π) r grows by 535.5 times. For the little I know the equation should be just r = e2π = 535.5 Supposing it starts at r=1cm and goes clockwise, I have guessed that its length should be 755.88 cm. and pitch=45° , but according to Torricella formula pitch should be ≈44.85°, since the whole length should be ≈ 759 cm and [itex]\varphi[/itex]= ≈45.15° so that 535.3/cos[itex]\varphi[/itex] =759 cm and 759-755.9 = 3 cm which is too much for the curve from 1 to 0, isn't it? Can anyone make a graph? Thanks a lot.