Photons of frequencies equal to the frequencies of $H_\beta$ and $H_{\infty}$ lines of hydrogen are incident on a photosensitive plate,whose threshold frequency is equal to the frequency of the $H_\alpha$ line of hydrogen. The ratio of the maximum kinetic energies of the emitted electrons is

When a photon of wavelength $3000 \ \mathring{A}$ is incident on a metal surface,the energy of the emitted electron is $0.5 \ eV$. If a photon of wavelength $2000 \ \mathring{A}$ is incident on the same metal surface,the energy of the emitted electron will be:

Given below are two statements:
Statement-$I$: The figure shows the variation of stopping potential $(V_0)$ with frequency $(v)$ for two photosensitive materials $M_1$ and $M_2$. The slope gives the value of $\frac{h}{e}$,where $h$ is Planck's constant and $e$ is the charge of an electron.
Statement-$II$: $M_2$ will emit photoelectrons of greater kinetic energy for incident radiation having the same frequency.
In the light of the above statements,choose the most appropriate answer from the options given below.

The work function of a metal is $1 \; eV$. Light of wavelength $3000 \; \mathring{A}$ is incident on this metal surface. The velocity of the emitted photo-electrons will be:

Maximum velocity of photoelectrons emitted by a metal surface is $1.2 \times 10^6\, m/s$. Assuming the specific charge of the electron to be $1.8 \times 10^{11}\, C/kg$,the value of the stopping potential in volt will be

In a photoelectric experiment,electrons are ejected from metals $X$ and $Y$ by light of intensity $I$ and frequency $f$. The potential difference $V$ required to stop the electrons is measured for various frequencies. If $Y$ has a greater work function than $X$,which one of the following graphs best illustrates the expected results?