question_answer

Figure (a) shows the variation of the stopping potential \[{{V}_{0}}\] with the frequency \[\left( \mathbf{v} \right)\] of the incident radiations for two different photosensitive materials \[{{M}_{1}}\] and \[{{M}_{2}}\] (i) What are the values of work functions for \[{{M}_{1}}\] and \[{{M}_{2}}\]? (ii) The values of the stopping potential for \[{{M}_{1}}\] and \[{{M}_{2}}\] for a frequency \[{{v}_{3}}(>{{v}_{02}})\]of the incident radiations are \[{{V}_{1}}\] and \[{{V}_{2}}\] respectively. Show that the slope of the lines equals \[\frac{{{V}_{1}}-{{V}_{2}}}{{{v}_{02}}-{{v}_{01}}}\]                        (a) (b)

Answer:

                (i) Work function of metal \[{{M}_{1}},\]\[{{W}_{1}}=h{{v}_{01}}\] Work function of metal \[{{M}_{2}},{{W}_{2}}=h{{v}_{02}}\] (ii) From Fig. (b), slope of \[V-v\]lines \[=\frac{AB}{BC}=\frac{{{V}_{1}}-{{V}_{2}}}{{{v}_{02}}-{{v}_{01}}}\]