Unification of weak and electromagnetic interactions was done by

Two parallel discs are connected by a rigid rod of length $L=0.5 \,m$ centrally. Each disc has a slit oppositely placed as shown in the figure. $A$ beam of neutral atoms is incident on one of the discs axially at different velocities $v$,while the system is rotated at an angular speed of $600 \,rev/s$,so that atoms only with a specific velocity emerge at the other end. Calculate the two largest speeds (in $m/s$) of the atoms that will emerge at the other end.

What phenomena of light can be explained on the basis of particle theory and wave theory of light?

Dual nature of light is exhibited by

When a monochromatic point source of light is placed at $0.1\, m$ from a photocell,the cut-off voltage and saturation current are $0.8\, V$ and $24\, mA$ respectively. If the same source is placed at $0.2\, m$ away from the photocell,then the cut-off voltage and saturation current will be:

Energy of an electron and a photon are equal. If the wavelength of the electron is $1\,\mathring{A}$,then the wavelength of the photon is approximately ............. $\mathring{A}$.