Find distance beyond the myopic farpoint

  • Thread starter Thread starter Petra de Ruyter
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AI Thread Summary
A myopic person has a far point of 150 cm and a near point of 20 cm, leading to confusion about the actual object distance when viewing objects beyond their far point. The thin lens equation is referenced, but there is uncertainty regarding its application due to the lack of clear information about the scenario, particularly whether the person is wearing corrective glasses. The discussion highlights the need for additional context to accurately determine the object distance, as the problem implies a situation where the person can see clearly at 20 cm but struggles with objects further away. Participants express doubt about the relevance of the near point in calculating the object distance. Overall, clarity on the conditions of the vision correction is essential for solving the problem accurately.
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Homework Statement


A myopic person has a far point of 150cm and can see objects clearly at 20cm near point. What is the object distance?

Homework Equations



Thin lens equation 1/f =1/d1-do.

The Attempt at a Solution



di = -150cm because it's on the left of the lens. do = should = infinity, but I needed to know what the actual object distance is...beyond the myopic farpoint. I'm not sure that the 20cm near point is relevant. Does this mean that the actual object distance is do=1/0 and rearrange to find the actual object distance. However I'm not sure how this would work.
 
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The first sentence makes sense, but the second one does not. It seems that there is some missing information. The first sententence tells us that this person's eye can forcus on objects within the range 20 cm out to 150 cm. Now all of a sudden the sencond sentence wants to know where the object is located? I get the impression that the rest of the missing information concerns a problem where this person has glasses on which produces an image of some object located outside this range?
 
Hi there
This is the question
"What is the object distance when a myopic person with a far point of 150 cm, can see near images clearly at 20 cm from the eye."

I keep thinking that I need more information.
 
The question might mean that the person is wearing glasses to enable her to see distant objects clearly, but now she is looking at an object which results in an image of it being formed 20 cm in front of the eye?
 

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