Short sight

Problem by zainul abidin
30 Nov 1999 00:00 WIB
One person with short sight has a far point 1 m from the eye and a near point 150 mm away. Explain why is it necessary to use a correcting lens with a power of -1 diophtry. An object placed 150 mm in front of this person's uncorrected eye is seen to be in focus. A pair of spectacles containing a correcting lens moves the near pint further from the eye. Work out how far the near point is now from the eye.