A telescope has an objective lens of 10 cm diameter and

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A telescope has an objective lens of 10 cm diameter and is situated at a distance of one kilometer from two objects. The minimum distance between these two objects, which can be resolved by the telescope, when the mean wavelength of light is 5000 Å, is of the order of

1. 5 cm
2. 0.5 m
3. 5 m
4. 5 mm

Correct Option: D

Here, =	x	=	1.22λ
	1000		D

or, x =	1.22 × 5 × 10³ × 10^-10 × 10³
	10 × 10^-2

or, x = 1.22 × 5 × 10^-3 m = 6.1 mm
∴ x is of the order of 5 mm.