Optionals IAS Mains Physics: Questions 145 - 149 of 307

Here of mercury column , , d

In accordance with Bernoulli՚s equation,

Where is the pressure at the second point.

Or

So that

Or

Whence,

of mercury column.

• When a strong beam of visible or ultra violet line – spectra light illuminates a gas, a liquid or a transparent crystal, a small fraction of light is scattered in all directions. The spectrum of the scattered light is found to consist of lines the same frequencies as that of the incident beam (Rayleigh lines) , and also certain weak lines of change…

or .

The rest mass of proton is

Hence its mass at velocity is given by

Hence its relativistic energy

Now as we know

Relativistic energy of the proton

To determine the momentum of the electron, we use the relation,

Whence

And

Substituting the value of , we have

Thus, the momentum of the proton .

• In all superconductors, the entropy decrease markedly on cooling below the critical temperature . Measurements for aluminum are plotted in Fig (1) . The decrease in entropy between the normal state and the superconducting state tells us that the superconducting state is more ordered than the normal state, for the entropy is a measure of the disorde…

• An atomic system is characterized by discrete energy states, and usually the atoms occupy the lowest energy state, known as the ground state. An atom in a lower energy state may be excited to a higher energy state through a number of processes, one process being absorption of electromagnetic radiation of proper frequency. On the other hand, an atom…