Question

me that the child's eyes are identical, with each reina lying A child's far point is 133 cm and her mer point is 11.5 cm In what follows, we assume that we can model the eye as a simple camers, with a single thin lens forming a real image upon the retina. We also 2.20 cm from the eye's nens." (a) What is the power of the eye when focused on the for point e r your answer is dites.) 272 X Refer to the thin-es equation. Recall the relationship between lens power and focal length. Recall the sin conventions for and ade car with units. diopters b) What is the power of the eye when focused upon the near point? (Enter your answer in diepers.) 233 Refer to the thin-lens equation, Recall the relationsh between ens power and focal length. Recall the conventions for and e. Be careful with units diepters (c) What power in diopters) must contact lens have in order to correct the child's sightedness? (Assume that the distance is infinit) e with inty, and the imageance with the Refer to the th point dance ation R athe relation bewure to make a negative, between lens power focal length Recall the the ages seen through a contenere all w convention for e are with Equate the object its diopters (d) Is this contact lens a converging or diverging lens dvere

Answer 1

- * Given that for Point = 133cm. Near Point = 11.5cm for Normal eye for point too and Near Point = 25cm. required focal length for Cospect far Point = tot if I f 182 133 Required Jocal length for Converging lens. 7 = 133 cm.) correct Near Point ! I tt t - i5 25 I= -25+ 11.5 25x12.5 -0.047 & divaging lens [+ = -21-27 cm) Power for for Point 12 = 1 / 100 = 0.750 power for Ner Point 1P = - = -100 = 4.700 t 133 21-27 © In Near sightedness, human eye can't see clear for object, (as it blurred) uto F = 133cm required lens = Co P 0.75D Net focal length 1 mes 3 + 1/ 133 * - 21:27 le fried = fire. it combine lems is Diverjing lens,