Question

The forbidden energy gap for 'Ge' crystal at '0' K is

• A. 2057 eV
• B. 0.071 eV
• C. 6.57 eV
• D. 0.71 eV

Answer 1

The Correct Option is D

Answer: The forbidden energy gap (band gap) for a germanium (Ge) crystal at absolute zero temperature (0 K) is approximately 0.71 eV. Therefore, the correct option is (D) 0.71 eV.

Explanation: 

The forbidden energy gap, also known as the band gap, is the energy difference between the valence band and the conduction band in a semiconductor. At absolute zero (0 K), the electrons are in the lowest energy state, and for germanium (Ge), this gap is approximately 0.71 eV. This is a key characteristic of the material that determines its electrical properties.

Therefore, the correct answer is: 0.71 eV (option D).

Answer 2

The forbidden energy gap, also known as the band gap, is a crucial property of semiconductors like germanium (Ge). It represents the energy range where no electron states can exist within the material. Electrons must gain enough energy to jump across this gap to become free charge carriers and contribute to electrical conductivity. 

The forbidden energy gap of germanium (Ge) is temperature-dependent. As the temperature decreases, the band gap generally increases slightly. At absolute zero (0 K), the forbidden energy gap for germanium is approximately:

0.74 eV

This value is important for understanding the behavior of germanium-based devices at very low temperatures. The band gap value influences various electrical and optical properties of the material.