Due to hyperopia, a person has a near point at 60 cm. What is the refractive power of the glasses prescribed to correct the sight?
A)-2.3 dpt
B)+2.3 dpt
C)-5.7 dpt
D)+5.7 dpt

Question

Quizplus · Accepted Answer

Hyperopia (farsightedness) means the person has difficulty focusing on close objects. The near point at 60 cm indicates the closest point at which objects can be seen clearly. To correct this, converging lenses are used, which have positive diopters. The refractive power (P) needed can be calculated using the formula P = 1/f, where f is the focal length in meters. To bring the near point to the standard 25 cm (0.25 m), the lens must have a focal length that allows the person to see clearly at this distance. Thus, P = 1/0.60 - 1/0.25 = 1.67 - 4 = -2.33, which is approximately +2.3 diopters, indicating a converging lens is needed.

Due to Hyperopia, a Person Has a near Point at 60