Question

The resolving power of telescope of aperture $100cm$ for light of wavelength $5.5\times {10}^{-7}m$ is ...............

• A. $0.149\times {10}^7$
• B. $1.49\times {10}^7$
• C. $14.9\times {10}^7$
• D. $149\times {10}^7$

Answer 1

Answer: (A)

$0.149\times {10}^7$

Aperture (diameter) of telescope $D=100cm=1m$

Wavelength of light $\lambda =5.5\times {10}^{-7}m$

Resolving power of telescope $RP=\frac{D}{1.22\lambda }$

$⟹$ $RP=\frac{1}{1.22\times 5.5\times {10}^{-7}}=0.149\times {10}^7$