The least resolvable angle by a telescope using an objective of aperture is nearly
sec
Step 1: Given Data
The objective aperture is is
Wavelength is
Step 2: Formula used,
Where is the wavelength
is the objective aperture
Step 3: Calculation
⇒
⇒
now we have to convert radians into degrees
⇒
⇒
⇒
Hence, the correct answer is option C