Q. 243.7( 3 Votes )

# Figure in the plot of the stopping potential versus the frequency of the light used in an experiment on photoelectric effect. Find (a) the ratio h/e and (b) the work function

Answer :

from the above graph we see that,

When =1.656V then …… (1)

When =0 then …. (2)

Where the stopping potential and ν is the frequency

Of the light.

From Einstein’s photoelectric equation,

….(3)

∴ from eq (1) & (3) we have

….. (4)

Again from eq(2) & (3) we have

…… (5)

On solving eq (4) & (5) we get

⇒

Work function,

Now, to find the ratio h/e we put the value of Ф

In eq (5) we get,

⇒

⇒

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