4 One wavelength of electromagnetic radiation emitted from a mercury vapour lamp is 436 nm.
(1) Calculate the photon energy corresponding to this wavelength.
A. 4.6x10-19 eV
B. 4.6x10-19)
C. 436x10-"')
D. 3.0x10-9 ev
(ii) Data for the work function energies of caesium and tungsten metal are given in Fig. 10.1
metal
work function
energy/eV
caesium
1.4
tungsten
4.5
From which surface will the electrons will be released, when the photon in problem (1) were
incident on the surfaces of cesium and tungsten?
A. Cesium
B. Tungsten
C. Both
D. non