Q. For an insulator the forbidden energy gap is
A) Zero
B) 1 eV
C) 5 eV
D) 2 eV
Explanation
(c) For an insulator $E_{g}$> 3 eV, that is why electron transition from valence band to conduction band is not possible. For semiconductor $E_{g}.$ is 0.2 eV to 0.3 eV while for metals $E_{g}$> 3 eV.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.