posted by lauren on .
You meet a person with prescription glasses of +1.74 dpt.
What is the near point of this person? Express the result as a positive number!
Hint: the near point of a healthy person is 25 cm. An object placed at this distance will form an image at the near point of the person.
i used m=-q/p and got 43.5...but the answer is 44.2 .. what am i missing here?!
They ask for a distance, presumably in centimeters. m = -q/p is a ratio.. presumably a magnification.
1.74 dpt (diopters) means that the 1/f value for the lens is 1.74 meters^-1
That seems to be what you are missing.