object distance p =infinity
image distance q = -70 cm
focal length f = ?
1/p + 1/q = 1/f
1/infinity - 1/70 = 1/f
focal langth f = -70 cm = -0.7 m
power of lens P = 1/f = 1/0.7 = -1.43 diopters
Exercise 31.33 Part A You're an optometrist helping a nearsighted patient who claims he can't see...
A particular nearsighted patient can't see objects clearly beyond 19.7 cm from their eye. Determine the lens power required to correct the patient's vision and the type of lens required (converging or diverging). Neglect the distance between the eye and the corrective lens. HINT (a) the lens power required to correct the patient's vision (in diopters) diopters (b) the type of lens required (converging or diverging) O converging Odiverging
Goal Apply geometric optics to correct nearsightedness. Problem A particular nearsighted patient can't see objects clearly when they are beyond 24 cm (the far point of the eye). (a) What focal length should the prescribed contact lens have to correct this problem? (b) Find the power of the lens, in diopters. Neglect the distance between the eye and the corrective lens. Strategy The purpose of the lens in this instance is to take objects at infinity and create an image...
An optometrist determines that a patient cannot clearly see any object that lies closer than 67.6 cm to the patient's eye. (a) Which of the following terms best describes this distance? Focal length, Near point, Far point, Magnification b)The patient needs to be able to clearly see objects that are just 23.0 cm distant. A contact lens is called for. What focal length (in cm) should this lens have? Assume the lens can be modeled as an ideal thin lens,...
A patient can't see objects closer than 32 cm and wishes to clearly see objects that are 18.3 cm from his eye. (a) Is the patient nearsighted or farsighted? (b) If the eye-lens distance is 1.92 cm, what is the minimum object distance p from the lens? in cm (c) What image position with respect to the lens will allow the patient to see the object? in cm (d) Is the image real or virtual? Is the image distance q...
An optometrist determines that a patient cannot clearly see any object that lies closer than 67.2 cm (a) Which of the following terms best describes this distance? far point ncar point magnification focal length (b) The patlent needs to be able to clearly see objects that are just 23.0 cm distant. A contact lens is prescribed. What focal length (in cm) should this lens have? Assume the lens can be modeled as an Ideal thin lens, which lies adjacent to the eye. (c) What is the power,...
A patient can't see objects closer than 32.5 cm and wishes to clearly see objects that are 20.0 cm from his eye. (a) is the patient nearsighted or farsighted? O nearsighted O farsighted (b) If the eye-lens distance is 2.05 cm, what is the minimum object distance p from the lens? (Give your answer to at least three significant digits.) cm (c) What image position with respect to the lens will allow the patient to see the object? (Give your...