$A$ metal having a work function of $4 \, eV$ is exposed to a photon of $\lambda = 1240 \, \mathring{A}$. If an accelerating potential of $7.6 \, V$ is applied,then the electron with maximum kinetic energy will have a speed equal to -

What is the amount of energy associated with the first orbit of a monopositive helium ion? $[R_{H} = 2.18 \times 10^{-18} \ J]$

If the potential energy of an electron in a hydrogen atom is $-3.02 \ eV$,then the electron is present in which of the following excited states?

Consider one $He^{+}$ ion is in excited state $(n = 5)$. Which of the following observations hold true as per the Bohr's model?

When electromagnetic radiation of wavelength $310 \ nm$ falls on the surface of a metal having work function $3.55 \ eV$, the velocity of photoelectrons emitted is $x \times 10^5 \ ms^{-1}$. The value of $x$ is (Nearest integer). Given: $m_{e} = 9 \times 10^{-31} \ kg$, $h = 6.63 \times 10^{-34} \ J \cdot s$, $c = 3 \times 10^8 \ m/s$, $1 \ eV = 1.6 \times 10^{-19} \ J$.

In the Balmer series of the hydrogen atom spectrum,which electronic transition causes the third line?