How to find the minimum angular resolution?

AI Thread Summary
To find the minimum angular resolution for a telescope observing ultraviolet light at a wavelength of 240 nm and a diameter of 2.40 m, the equation θ = 1.22 λ/D is used. The calculated angular resolution is 1.99 * 10^-7 radians, which is consistent with the parameters provided. There was confusion regarding a book's answer of 7 * 10^6, deemed incorrect due to its implausibility. A typo was acknowledged in the discussion, confirming that the correct calculation yields 1.22. The final conclusion is that the initial calculation is accurate.
Nat1234123
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Homework Statement


λ = 240 nm
D = 2.40 m
We are supposed to find the angle resolution (minimum angular distance between two objects so we
still see them as two separate objects) to the telescope for ultraviolet light with wavelength 240 nm

Homework Equations


The equation that I used is θ = 1.22 \frac{λ}{D}

The Attempt at a Solution


θ = 1.22 \frac{λ}{D} and putting the values in, in meters. However, my answer was 1.99 * 10^-7, the answer according to the book is 7 * 10^6
 
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Obviously, the answer in the book is wrong. You can't have an angular resolution that high. In fact you can't have an angular resolution greater than π. How did you get 1.99 from 1.22? What is the ratio 240 nm/2.4 m?
 
kuruman said:
Obviously, the answer in the book is wrong. You can't have an angular resolution that high. In fact you can't have an angular resolution greater than π. How did you get 1.99 from 1.22? What is the ratio 240 nm/2.4 m?
Sorry, it was a typo. I did get 1.22, my apologies.
 
Nat1234123 said:
Sorry, it was a typo. I did get 1.22, my apologies.
Then your answer is correct.
 
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