Question

The diameter of the objective of the telescope is 0.1 metre and wavelength of light is 6000 Å. Its resolving power would be approximately

• A. $7.32 \times 10^{- 6}rad$
• B. $1.36 \times 10^{6}rad$
• C. $7.32 \times 10^{- 5}rad$
• D. $1.36 \times 10^{5}rad$

Answer 1

Answer: (D)

$1.36 \times 10^{5}rad$

Answer 2

Resolving power

$= \frac{d}{1.22\mspace{6mu}\lambda} = \frac{0.1}{1.22 \times 6000 \times 10^{- 10}}$

$\cong 1.36 \times 10^{5}radian$