Question

Which of two surfaces x and y has greater work function and why?

Answer 1

Answer:

(i) Einstein’s photoelectric equation

hν = φ+eV

V  = hν/e + φ/e              …(i)

Equation (i) represents a straight line given by line P andQ.  φ/e  represents negative intercept on the Y-axis. Since,Q has greater negative intercept, it will have greater φ (work function) and hence higher threshold frequency.

 

(ii) Also from  

W  = hv0  work function of Q is  6 x 1014 x 6.63 x 10-34

W = 3.9 x 10-19 unit WQ > WP

(iii) Emax  =  hv - φ0 = hv - hv0 = h(v-v0)

= 6.63 (8x1014  -  6x1014) J x 10-34J  

= 1.33 x 10-19 J

Step-by-step explanation: