The maximum wavelength of electromagnetic radiation, which can create a hole-electron pair in germanium. (Given that forbidden energy gap in germanium is 0.72 eV)

Options

A. 172220 Å
B. 172.2 Å
C. 17222 Å
D. 1722 Å

Answer

C

Explanation

Energy gap, `E_(g)=(hc)/(lambda) and lambda=(hc)/(E_(g))=(12400)/(0.72)=17222`Å