The thermal conductivity of a crystal is 10 W/mK. What is the phonon mean free path if the specific heat is 100 J/kgK and the sound velocity is 5000 m/s?
Q1. The thermal conductivity of a crystal is 10 W/mK. What is the phonon mean free path if the specific heat is 100 J/kgK and the sound velocity is 5000 m/s?
Answer: 20 nm
Explanation: Using K = (1/3) * C_v * v * λ, we can find λ = 3K / (C_v * v).