Radiation with a wavelength of 238 nm shines on a metal surface and ejects electrons that have a maximum speedof 3.75 X 105 m/s.
Which one of the followingmetal is it, the calues in paretheses being the work functions:
a) potassium (2.24 eV)
b) calciun (2.71 eV)
c) uranium (3.63 eV)
d) aluminium (4.08 eV)
e) gold (4.82 eV)
