A laser pulse of energy 4 mJ and the pulse duration 1.5 ns is focused on a target of radius 0.02 mm. What is the laser intensity?

Molybdenum has a work function of 4.20 eV. What is the stopping potential if the incident light has a wavelength of 180 nm?

B4. A bone sample has a density p = 1.2x10³ kg/m³, a molar mass m = 217 g/mol and an interaction cross section per atom o = 6.0x10-22 cm². Determine the linear attenuation coefficient µ (in cm-¹) and the half value layer (in cm). Assume there is no scattering when the radiation interacts with the bone sample. Express the values to 3 significant figures, if necessary.

When we illuminate lead with ultraviolet light with a wavelength of 250 nm, suppose we find the maximum potential difference developed between the plates in the experimental setup shown in the figure to be 0.82 volts. From these data and the accepted value of hc, find the potential difference between the plates if the wavelength is 215 nm. Also find W for lead.

A laser emits a pulse of light with wavelength 532 nm. If the total energy contained in the pulse is 1.2 J, the number of photons in the pulse is?

The threshold frequency of a polished metal surafce is 8.80 x1014Hz. The work function of the surface is? _eV