A farsighted person has a near point distance greater than the ...

[2125004343]

A farsighted person has a near point distance greater than the normal distance of 25 cm. Neglecting the eye-lens distance, which approach will yield an appropriate corrective lens for this condition?
  1.The corrective lens should have a focal length equal to the normal near point distance, i.e., 25 cm.
  2.The corrective lens should have a negative focal length equal in magnitude to the normal near point distance, i.e., 25 cm.
  3.The corrective lens should make an object at a distance equal to the near point appear to the eye to be at a distance of 25 cm.
  4.The corrective lens should make an object at a distance of 25 cm appear to the eye to be at a distance of the near point.

Question 2

Camera 1 has a lens of diameter 2.0 cm with a focal length of 5.0 cm, camera 2 has a lens of diameter 1.5 cm with a focal length of 4.5 cm, and camera 3 has a lens of diameter 1.1 cm with a focal length of 3.3 cm. Assuming all the cameras use the same type film and have a shutter speed of 1/200 s, which camera can give the best exposure at the lowest light level?
  1.3
  2.2
  3.2 and 3 are both equal and better than 1.
  4.1

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Answer to Question 1

4

Answer to Question 2

4

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Thanks for the timely response, appreciate it

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