Question

The work function of a certain material is 4.9 eV. What is the photoelectric minimum (threshold) frequency for this material?

A. 1.18 x 10¹⁵ Hz

B. 2.23 x 10¹⁵ Hz

C. 9.01 x 10¹⁴ Hz

D. 3.48 x 10¹⁵ Hz

E. 2.56 x 10¹⁵ Hz

Answer 1

$W=h\nu\to\nu=W/h=4.9\cdot1.6\cdot10^{-19}/(6.62\cdot10^{-34)}=1.18\cdot10^{15}\ (Hz)$

A. $1.18\cdot10^{15}\ (Hz)$ . Answer