How to read log scale?

Answer 1

Log scales have there scales exponentially written. They are used to provide a detailed line for smaller values when on a normal graph this would be hard to see as they are too small. Most Log Scales use base 10, so this tutorial is for that. If your log scale uses a different base (it will not be segmented by multiples of 10, eg: 0.1, 1.0, 10, 100), just substitute your number in. 1. On the x scale identify where your number lies. Mine lies between 10 and 100. 2. Find the ratio your number is along your section of the log scale. So I measure the distance from 10 to my number and divide it by the distance from 10 to 100. The distance to my number from 10 = 20 mm The distance to 100 from 10 = 100 mm Therefore the ratio = 20/100 = 0.2 3. Find the value of your number by this formula: 10^(ratio) x previous log marker For me this = 10^0.2 x 10 = 1.585 x 10 = 15.85 4. You're done! your answer is 15.85 (x scale units). Another example: your value lies 3/4 of the way between 0.01 and 0.1 =10^0.75 x 0.01 = 5.623 x 0.01 = 0.0056