exam1_2002 - Name: _ 2.57 Midterm Exam No. 1 Fall, 2002 1....

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Name: ____________________ 2.57 Midterm Exam No. 1 Fall, 2002 1. Answer the following ten short questions. Briefly explain your answer ( 60 Points ). (1) Diamond has an fcc structure with a lattice constant (conventional unit cell) of 3.57 Å, calculate the density of diamond. (2) The fundamental vibrational frequency of H 2 is 1.3x10 14 Hz, estimate the effective spring constant between the two hydrogen atoms (note: normal hydrogen atom has only one proton and does not have a neutron). (3) Light is emitted between the first two energy levels of a 60 Å wide one-dimensional quantum well with infinite potential barrier height, what is the wavelength of the light?
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Name: ____________________ (4) At high temperature limit, each mode of lattice vibration has an average energy of k b T/2. What is the total vibrational energy per unit volume for a silicon crystal at 1000 K. Silicon has an fcc lattice with a lattice constant of 5.43 Å. (5)
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/27/2012 for the course MECHANICAL 2.57 taught by Professor Gangchen during the Fall '04 term at MIT.

Page1 / 4

exam1_2002 - Name: _ 2.57 Midterm Exam No. 1 Fall, 2002 1....

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online