Question

An experimenter finds that no photoelectrons are emitted from a particular metal unless the wavelength of light is less than 295 nm. her experiment will require photoelectrons of maximum kinetic energy 2.4 ev. what frequency light should be used to illuminate the metal?

Answer 1

if the object, ends up with a positive charge, then it is missing electrons. if it is missing electrons, then it must have been removed form the object during the rubbing process.