Options:
A.
B.
C.
D.
Sign in to view the correct answer and detailed explanation.
Study with fewer interruptions on Android
Use Ulearngo on a verified device for smoother past-question study.
Ulearngo is an independent study app. It is not affiliated with, endorsed by, or representing Joint Admissions and Matriculation Board (JAMB). Always confirm official exam, admission, registration, syllabus, timetable, and result information from JAMB official website.
Earlier discussion
1 older comment kept for context.
Oluwaseun Adeyemi
For an electron to be liberated from the surface of a metal the frequency or wavelength of the incident light must be greater than the threshold frequency (fo) or wavelength (λo ). The intensity of the radiation determines the number of electrons liberated but the frequency or wavelength of the incident radiation determine the kinetic energy of the ejected electron.
hf = wo + K.E
But W_o = hfo and K.E = ev
K.E = ev = hf - wo = hf - hfo
ev = h(f - fo)
Therefore f > fo for electron to be liberated.