With the help of telescope that has an objective of diameter 200 cm. it is proved that ligh of wavelengths of the order of 6400 `Å` coming from a star can be easily resolved. Then, the limit of resolution is

Options

A. `39xx10^(-4)deg`
B. `39xx10^(-8)rad`
C. `19.5 xx10^(-8) rad`
D. `19.5xx10^(-8)deg`

Answer

B

Explanation

`theta=(1.22lambda)/(d)`
`lambda=6400A^@ =6400xx10^(-10)m`
`d=200cm=2m`
`theta=1.22xx6400xx10^(-10)/(2)`
`theta=3.9xx10^(-7)`
`theta=39 xx10^(-8)` rad.