The diameter of moon is 3.5×10^3km and its distance from the earth is 3.8×10^5km. If it is seen through a telescope whose focal length for objective and eye lens are 4 m and 10 cm respectively, then…

Question

The diameter of moon is 3.5×10^3km and its distance from the earth is 3.8×10^5km. If it is seen through a telescope whose focal length for objective and eye lens are 4 m and 10 cm respectively, then the angle subtended by the moon on the eye will be approximately

Accepted Answer

Correct answer: B. (b) The angle subtended by the moon on the objective of telescope α= 3.5×10^33.8×10^5= 3.53.8×10^−2rad Also ⇒ 40010= βα ⇒ β=40 α ⇒ β=40× 3.5×10^33.8×10^5× 180π=20°

$The diameter of moon is 3.5 \times 1 0^{3} k m and its distance from the earth is 3.8 \times 1 0^{5} k m . If it is seen through a telescope whose focal length for objective and eye lens are 4 m and 10 cm respectively, then the angle subtended by the moon on the eye will be approximately$

Solution

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