Why is magnification defined as the ratio of eye and objective lens resolution?

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    Magnification Telescope
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Discussion Overview

The discussion centers on the definition of magnification in telescopes, specifically questioning why it is expressed as the ratio of the resolution power of the eye to that of the objective lens. Participants seek justification for this definition and explore related concepts of resolving power.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant states that telescope magnification is defined as the measure of the resolution power of the eye divided by that of the objective lens, seeking justification for this definition.
  • Another participant questions the source of this definition and requests justification, referencing Wikipedia.
  • A third participant suggests consulting a specific physics textbook for further clarification on the topic.
  • A later reply challenges the initial definition, asserting that magnification is actually defined as the ratio of the focal lengths of the telescope and the eyepiece, and questions the clarity of the concept of resolving power in this context.
  • This same participant expresses uncertainty about the initial participant's understanding of the text, suggesting a possible misunderstanding or analogy rather than a precise definition.

Areas of Agreement / Disagreement

Participants do not appear to agree on the definition of magnification, with competing views on whether it should be based on resolving power or focal lengths. The discussion remains unresolved regarding the justification of the initial claim.

Contextual Notes

There is ambiguity regarding the definition of resolving power, and the discussion highlights the need for clarity on how this concept is applied in the context of magnification.

Marketo
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The telescope magnification is given by the measure of the resolution power of the eye divided by the resolution power of the objetive lens. I just want to know why a magnification can be defined as the ratio of these two kinds of resolution, I need a justification of this statement.
 
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xts said:
Where have you found such definition of magnification?
I would also like to see its justification

See: http://en.wikipedia.org/wiki/Magnification

Please check The physics book of Marcelo Alonso and Edward J. Finn in the chapter of geometry of waves when talking about telescope
 
Marketo said:
Please check The physics book of Marcelo Alonso and Edward J. Finn in the chapter of geometry of waves when talking about telescope
Ouch - you are sending me to a library having English science textbooks (it had not been translated to my language, so I won't get it in my local library)... Not this week...
 
Marketo said:
The telescope magnification is given by the measure of the resolution power of the eye divided by the resolution power of the objetive lens. I just want to know why a magnification can be defined as the ratio of these two kinds of resolution, I need a justification of this statement.

It is not defined this way, it is defined as the ratio of focal lengths of the telescope and the eyepiece. Resolving power is not a clearly defined concept unless you also state how you define resolving power, and in any case it makes no sense in this context. Either you misunderstood the text and did not look into it any farther, or the text is making some kind of analogy or stating how (I don't know how) the precisely defined number "magnification" can be stood in terms of resolving power of the two components. I also presume you meant "eyepiece" when your wrote "eye".
 

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