Diameter of the objective of a telescope is 200 cm. What is the resolving power of a telescope ? Take wavelength of light `=5000 Å`.

Options

A. `1xx10^(6)`
B. `6.56xx10^(6)`
C. `3.28xx10^(6)`
D. `3.28xx10^(5)`

Answer

C

Explanation

Here,
Diameter of the objective,
`D=200 cm = 200 xx 10^(-2)m = 2 m `
Wavelength of light,
`lambda=5000 Å=5000xx10^(-10)m = 5 xx 10^(-7)m`
Resolving power of a telescope`=(D)/(1.22lambda)`
`=(2)/(1.22xx5xx10^(-7))=(4)/(1.22)xx10^(6)=3.28xx10^(6)`