Assume that light of wavelength $600\, nm$ is coming from a star. The limit of resolution of a telescope whose objective has a diameter of $2\, m$ is $......... \times 10^{-7}\, rad$.

The average distance between the earth and moon is $38.6 \times 10^4 \ km$. The minimum separation between the two points on the surface of the moon that can be resolved by a telescope whose objective lens has a diameter of $5 \ m$ with $\lambda = 6000 \ \mathring{A}$ is ...... $m$.

$A$ person is observing a bacteria through a compound microscope. For better analysis and to improve the resolving power,he should:

Two parallel pillars are $11 \, km$ away from an observer. The minimum distance between the pillars so that they can be seen separately will be.....$m$

$A$ telescope of aperture $3 \times 10^{-2} \, m$ diameter is focused on a window at $80 \, m$ distance fitted with a wire mesh of spacing $2 \times 10^{-3} \, m$. Given: $\lambda = 5.5 \times 10^{-7} \, m$,which of the following is true for observing the mesh through the telescope?

How to increase the resolving power of a telescope and a microscope?