# Physics

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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?!

• Physics -

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.

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