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E=hc/wavelength
= (6.63 x 10^-34)(3.0 x 10^8)/(4.3 x 10^-7)
=4.626 x 10^-19 J
Potassium. The reason being the work function of potassium is lower than the energy of incident radiation.
E= w0 + K.E.
K.E. =E-W0
=4.63 x 10^-19 -3.68 x 10^-19
=9.46 x 10^-20 J
½ meV^2 =9.46 x 10^-20
V =v(2.087 X 10^11)
=4.569 x 10^5 m/s
joseph rimiru answered the question on December 10, 2017 at 18:27
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