Exercise

A thin converging lens of focal length $5cm$ is used as a simple microscope.
Calculate its magnifying power when image formed lies at:
(a) Infinity.

A thin converging lens of focal length 5cm is used as a simple microscope.
Calculate its magnifying power when image formed lies at:
(b) Least distance of distinct vision

A thin converging lens of focal length $12 \mathrm{cm}$ is kept in contact with a thin diverging lens of focal length $18 \mathrm{cm}$. Calculate the effective/equivalent focal length of the combination.

Name the process that causes depletion region in p-n junction.

Using Huygens' wave theory of light, prove Snell's law if refraction of light. 

In Young’s double slit experiment, what should be the phase difference between the two overlapping waves to obtain$5th$dark band/fringe on the screen?

On the basis of Bohr's theory, derive an expression for the radius of the $n^{th}$ orbit of hydrogen atom.

Name the diode that emits spontaneous radiation when forward biased.