## Question

The diameter of the moon is 3.5 × 10^{3} km and its distance from the earth is seen by a telescope, having the focal lengths of the objective and the eye-piece as 4m and 10 cm respectively; the diameter of the image of the moon will be approximately:

### Solution

21^{o}

As the angle subtended by moon on the objective of telescope

the angular size of final image

#### SIMILAR QUESTIONS

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