A telescope mirror with diameter $D = 200$ inches observes a star emitting $\lambda = 5000$ Å. Its angular limit of resolution is approximately:
A$1.2 \times 10^{-7}$ rad
B$1.2 \times 10^{-5}$ rad
C$1.2 \times 10^{-3}$ rad
D$0.5$ arcsec
Answer & Solution
Correct answer: A. $1.2 \times 10^{-7}$ rad
200 inches = 5.08 m. $\theta = 1.22\lambda/D = 1.22 \times 5 \times 10^{-7}/5.08 \approx 1.20 \times 10^{-7}$ rad. (Hale telescope-scale.)
Related questions
Newton originally supported the corpuscular theory of light. The wave theory was strongly In a Young's double-slit experiment, a thin transparent sheet of thickness t and refractivCoherent sources are those that emit waves ofIf polarised light of intensity I passes through a polariser whose axis makes angle θ withAn unpolarised light of intensity I₀ passes through a polariser. The transmitted intensityWhich of the following phenomena is characteristic ONLY of transverse waves and NOT of lonThe polarising angle (Brewster angle) for glass of refractive index 1.5 isThe width of the central maximum in single-slit diffraction on a screen at distance D is