A 5 watt LED bulb converts 80% of the power into light photons of wavelength 660nm. What is the number of photons emitted from the bulb in one second ?
Light falls on a magnesium surface. The work function of magnesium is 3.68 eV.
Find the minimum frequency of the light source required to eject the
photoelectrons. Can the photoelectrons be ejected by increasing the intensity of
the light source? Why?
A laser of wavelength 532 nm is shot through a double slit at a screen 4.4 m away. If the separation between slits is 0.69 mm, what is the spacing between the fringes resultant on the screen?
light quanta of energy 3.5*10^-19J falls on cathode of phto cell the current through cell is reduced to zero by applying potential difference of 0.25Vwhat is work function of cathode