Question

A telescope is used to observe two distant objects 15 km away. If the separation between the objects is 1.5 m and they are illuminated by light of wavelength 600 nm, the diameter of the objective lens of the telescope to just resolve the objects will be, 1.7.32x10-30 2.7.32x10-2 cm 3. 7.32 cm 4732x101 cm​

Answer 1

Explanation:

5 mm

We know,

Resolving Power = θ=

D

d

but θ≈

a

λ

(Note:exact relation,θ=

a

1.22

λ)

D

d

=

a

λ

⇒=d=

a

λD

⇒d=

10×10

−2

5000×10

−10

×10

3

=5mm