Which one of the following frequencies of radiation (in $Hz$) has a wavelength of $600 \ nm$?

Assuming that the incident radiation is capable of ejecting photoelectrons from all the given metals,the lowest kinetic energy of the ejected photoelectron is observed with which of the given metals?

The velocity of $\alpha-$rays is approximately

The wavelength range of the visible spectrum extends from violet $(400 \, nm)$ to red $(750 \, nm).$ Express these wavelengths in frequencies $(Hz).$ $(1 \, nm = 10^{-9} \, m)$

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

Which of the following is not an electromagnetic radiation?