The eyes of certain reptiles pass a single visual signal to the brain when the visual receptors are struck by photons of a wavelength of 855 nm. If a total energy of 2.87 ✕ 10−14 J is required to trip the signal, what is the minimum number of photons that must strike the receptor?

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.

its first and third is your answer i did the qustion the fourth isnt right