The series limit for the Balmer series of $H$ atom spectra is:

$A$ surface ejects electrons when hit by green light but not when hit by yellow light. Will electrons be ejected if the surface is hit by red light?

Bohr's model can explain:

Which electron transition in a hydrogen atom requires the largest amount of energy?

For a $H$-atom,what is the wavelength in $nm$ associated with the transition of an electron from an infinite energy level to the first energy level? (Rydberg constant = $1.097 \times 10^{7} \ m^{-1}$)

The number of photons emitted by a monochromatic (single frequency) infrared range finder of power $1 \, mW$ and wavelength of $1000 \, nm$,in $0.1 \, s$ is $x \times 10^{13}$. The value of $x$ is ..... .
(Nearest integer)
$(h=6.63 \times 10^{-34} \, J \, s, c=3.00 \times 10^{8} \, m \, s^{-1})$