To which regions of the EM spectrum do the following wavelengths belong:

a) 250 nm
b) 1500 nm

12.

What is the difference between polarised light and unpolarized light?

Name the principle on the basis of which optical fibres work?

Calculate dispersive power of a transparent material given by:

n_v = 1.56, n_r = 1.54, n_y= 1.55

What is meant by short-sightedness?

Two metals A and B have work functions 4 eV and 6 eV respectively. Which metal has lower threshold wavelength for photoelectric effect.

Calculate angular momentum of an electron in the third Bohr orbit of hydrogen atom.

In a nuclear reactor, what is the function of a moderator?

In our nature, where is the nuclear fusion reaction taking place continuously?

What is the use of a Zener diode?