The hydrogen spectrum from an incandescent source of hydrogen is:

The blue colour of water in the sea is due to

In the photoelectric effect,the saturation photocurrent:

The energy of one mole of photons of radiation of wavelength $300 \ nm$ is ...... $kJ \ mol^{-1}$. (Given: $h = 6.63 \times 10^{-34} \ J \ s, N_A = 6.02 \times 10^{23} \ mol^{-1}, c = 3 \times 10^8 \ m \ s^{-1}$)

The energy of one mole of photons of radiation whose frequency is $5 \times 10^{10} \, s^{-1}$ is .......... $J$.

Arrange the following types of radiation in increasing order of frequency:
$(a)$ radiation from microwave oven
$(b)$ amber light from traffic signal
$(c)$ radiation from $FM$ radio
$(d)$ cosmic rays from outer space
$(e)$ $X$-rays