# Angular Magnification

by A_lilah
Tags: angular, magnification
 P: 54 1. The problem statement, all variables and given/known data If you have normal vision and are properly using a magnifying glass with a refractive power of 12.5 diopters, how far should you hold it from the object to achieve maximum angular magnification? 2. Relevant equations 1 diopter = 1/focal length = m^-1 M=angular magnification Mmax = [(Near Point)/f] +1 Near point for someone with normal vision = 25cm 3. The attempt at a solution First I use 12.5 diopters to figure out the focal length: 1/12.5 = .08m = 8cm Then I plugged this into the equation for Mmax for someone with normal vision: [25cm / 8cm] + 1 = 4.125 = Mmax I don't know how to use any of this to find the maximum distance the object should be held at though. The prof already posted the answers-this should be 6.67 cm- I'm just trying to practice before an exam and learn how to do this, so any help/tips would be great. Thanks!
 P: 4 Maybe you can use this: M = (f-v)/f 4.125 = 8-v/8 v = 25cm I am not so sure abt the answer. Another formula that you might find useful is M = f/(f+u)

 Related Discussions Advanced Physics Homework 0 Introductory Physics Homework 3 Introductory Physics Homework 1 Introductory Physics Homework 2 Introductory Physics Homework 1