Question

The work function of a photoelectric material is 3.3 eV. It threshold frequency will be:

• A. $8\times {10}^{14}Hz$
• B. $8\times {10}^{10}Hz$
• C. $5\times {10}^{33}Hz$
• D. $4\times {10}^{11}Hz$

Answer 1

The correct option is A $8\times {10}^{14}Hz$

Threshold frequency :- frequency of minimum energy required to remove electron

$workfunction=3.3ev$

$f=\frac{3.3\times 1.6\times {10}^{-19}J}{6.626\times {10}^{-34}J-s}$

$=0.8\times {10}^{15}Hz$

$=8\times {10}^{14}Hz$