Question

Assume that light of wavelength $600\, nm$ is coming from a star. The limit of resolution of telescope whose objective has a diameter of $2\,m$ is :

• A. $3.66 \times 10^{-7} \,rad$
• B. $1.83 \times 10^{-7} \,rad$
• C. $7.32 \times 10^{-7} \,rad$
• D. $6.00 \times 10^{-7} \,rad$

Answer 1

Answer: (A)

Limit of resolution,
$\theta_{R}=1.22 \frac{\lambda}{d}$;
$\lambda=600 \times 10^{-9}\,m$
$d=2\,m$
$\theta_{R}=\frac{1.22 \times 600 \times 10^{-9}}{2}$
$\theta_{R}=3.66 \times 10^{-7}$ rad