For a certain metal, light of frequency 7.24 × 10-14 Hz is just barely able to dislodge photoelectrons from the metal
(h = 6.626 × 10-34 J ? s, 1 eV = 1.60 × 10-19 J, e = 1.60 × 10-19 C)
(a) What will be the stopping potential if light of frequency 8.75 × 10-14 Hz is shone on the metal?
(b) What is the work function (in electron-volts) of this metal?
(a) 0.625 V (b) 3.00 eV
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