A simple telescope, consisting of an objective of focal length `60 cm` and a single eye lens of focal length `5 cm` is focussed on a distant object is such a way that parallel rays comes out from the eye lens. If the object subtends an angle `2^(@)` at the objective, the angular width of the image.A. `10^(@)`B. `24^(@)`C. `50^(@)`D. `1//6^(@)`

A simple telescope, consisting of an objective of focal length `60 cm`

1.	A simple telescope, consisting of an objective of focal length `60 cm` and a single eye lens of focal length `5 cm` is focussed on a distant object is such a way that parallel rays comes out from the eye lens. If the object subtends an angle `2^(@)` at the objective, the angular width of the image.A. `10^(@)`B. `24^(@)`C. `50^(@)`D. `1//6^(@)`
Answer» Correct Answer - B Since `m=(f_(o))/(f_(e))` Also `m=("Angle subtended by the image" )/("Angle subtended by the object")` `:. (f_(o))/(f_(e))=(alpha)/(beta)impliesa=(f_(o)xxbeta)/(f_(e))=(60xx2)/(5)=24^(@)`

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