Question

The maximum speed of photoelectrons ejected from the surface of a metal is 4.07E5 m/s, when light with a wavelength of 185 nm is shined on the surface. What is the work function of the metal? 0 2.40 ev 0 5.17 eV O 6.24 eV 0 4.70 eV O 1.42 eV Ei

Answer 1

Consider the Given data as shown below: max. feed of photoek ofrons. ()= 4.07x105 m/s www.long th ( ^) » [85mm (X) = 185x200 m Now, determine the works e function (w) by using following formula as shown TE below! E= wt KE W = E-KE

(W) = hxc hoxe - me OOOO ooo (1) where he plank constant 6.63x10 34 (Jis) ca speed of light = 3x108 m/s mass of eketsons 9. 14/0 34 kg put the value value of h, c, d, m, vin Eqn(1) ap shown belowit (W)= 6.630/634 x3x/08 9.1x1031 x(407X105)2 185x169 2 (W) = -20 (1.075x 15") – 7.537 xlo

(W) = 9.9963x1019 Change (J into ev, as shown below:- (9.996 x 1019 ev (0) 1.6x1039 (کا) 6.24 ev.Ang Cosy). Therefore, The work-function of the metal is, (W) = 6.24 ev So, is Correct option ses Goauer