Electrons are emitted with zero velocity from a metal surface when it is exposed to radiation of wavelength 6800 Å. Calculate threshold frequency (v0) and work function (W0) of the metal.
Given λ = 6800 amgstrom or 6800x 10-10 m = 6.8 x 10-7m
C = 3 x 108 m/s
Also λ = c/v or v = c/ λ Therefore putting the values in the equation, we get
=3 x 108 / 6.8 x 10-7m = 4.41 x 1014 s-1
Hence, work function (W0) of the metal = hν0
= (6.626 × 10–34 Js) (4.41 × 1014 s–1)
= 2.922 × 10–19 J
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(iii) 100 atoms of A + 100 molecules of B
(iv) 5 mol A + 2.5 mol B
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Thanks
Work function=h*threshold frequency Not h*frequency
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velocity of light
c is what and how 3*10*8