Single Choice

The angular resolution of telescope of 10 cm diameter at a wavelength of 5000 $${ A }^{ \circ }$$ is of the order of :

A$$ 10^{ 6 }rad$$
B$$ 10^{ -2 }rad$$
C$$ 10^{ -4 }rad$$
D$$ 10^{ -6 }rad$$
Correct Answer

Solution

Two point sources are regarded as just resolved when the principal diffraction maximum of one image coincides with the first minimum of the other.
If one considers diffraction through a circular aperture, this translates into the expression

θ=1.22
λ
d

=1.22×
5000×10−8
10

=1.22×5×10−6=6×10−6rad

Hence, the closest option is 10−6rad


SIMILAR QUESTIONS

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