This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Adv. EE II – Introduction to Electronics Course 300212 Spring term 2009 M. Bode Date: Apr. 02, 2009 Due: Apr. 16, 2009, in class Homework 5 This HW is about a simple analogue to atoms arranged in a crystal. The goal is to understand the basic mechanisms behind energy bands. As usual, do not forget to provide proper arguments for your conclusions. Task 1 (60) Band Structure (open ends) Consider a simple harmonic pendulum without damping: This describes the oscillating pendulum where x denotes the deviation of the pendulum from its equilibrium position as a function of time, and is its intrinsic or eigenfrequency. a) (10) Re-write the second order ode above as a pair of first order odes. To this end, introduce a new dynamical variable ( ) ( ) 2 t x t x ω − = ¡ ¡ ω v ¡ = . Then find equations for and v in terms of x and v : b) (10) The equations you found should be linear ones. So you may write them in matrix notation: Find the corresponding matrix M and its eigenvalues x ¡ ¡ ( ) ( ) v x g v v x f x , , = = ¡ ¡ = v x M v x ¡ ¡ 1 λ and 2 λ . What is the unit of such an eigenvalue? How are the eigenvalues related to the eigenfrequency of the pendulum? ( ) ( ) t x t Adv. EE II – Introduction to Electronics Course 300212 Spring term 2009 M. Bode Date: Apr. 02, 2009 Due: Apr. 16, 2009, in class c) (20) Now, consider a pair of identically built pendulums that are coupled by means of an elastic springs: As above, introduce velocities v ( ) ( ) ( )...
View Full Document
This note was uploaded on 05/04/2010 for the course CS 320142 taught by Professor Stamerjohans during the Spring '10 term at Jacobs University Bremen.
- Spring '10
- C++ Programming