How do I find/calculate the radius of curvature of a convex lens? [closed]

I have a convex lens, and I want to calculate it´s radius of curvature. It´s focal length is 24cm. how do I do it?

• You need to find out what it's made of (or otherwise find its refractive index out) then use the lensmaker's equation. – WetSavannaAnimal Jun 20 '17 at 13:36
• The lens is made out of glass (I took it out from a magnifiyng glass). What is the lensmaker´s equation? – Jlopez20 Jun 20 '17 at 13:40
• There are heaps of different lens glasses of vastly different indices. If you want a hazard a guess, go with Borofloat, soda glass or N-BK7. All of which have $n\approx1.5$. – WetSavannaAnimal Jun 20 '17 at 13:43
• Ok, then what is the lensmaker´s equation, and how do I use it? – Jlopez20 Jun 20 '17 at 13:48
• This is the lensmaker's equation – John Rennie Jun 20 '17 at 15:34