engineering physics MCQ #5185

The effective mass of an electron in a crystal is

engineering physics MCQ #5185

  1. Question 1

    Q1. The effective mass of an electron in a crystal is

    • A) always positive
    • B) always negative
    • C) sometimes negative
    • D) zero

    Answer: sometimes negative

    Explanation: Effective mass can be negative near the top of the band due to the curvature of E-k diagram, a concept from solid-state physics.