MCQ
Work function of a metal is $2.51 eV$. Its threshold frequency is
- A$5.9 \times {10^{14}}cycle/sec$
- B$6.5 \times {10^{14}}cycle/\sec $
- C$9.4 \times {10^{14}}cycle/\sec $
- ✓$6.08 \times {10^{14}} cycle/sec$
✓
Answer
Correct option: D.
$6.08 \times {10^{14}} cycle/sec$
d
(d) ${W_0} = h{\nu _0}\,$
(d) ${W_0} = h{\nu _0}\,$
$\Rightarrow \,\,{\nu _0} = \frac{{{W_0}}}{h} = \frac{{2.51 \times 1.6 \times {{10}^{ - 19}}}}{{6.6 \times {{10}^{ - 34}}}}$
$ = 6.08 \times {10^{14}}\,Cycle/\sec .$
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