EAD234B_Homework2_2010

EAD234B_Homework2_2010 - EAD 234B: E&M Homework...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon

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

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: EAD 234B: E&M Homework #2 Due Thursday, April 15, 2010 (1) Assume that the ionosphere may be modeled as a plane-stratified plasma (n e ∝ height) with B = 0. Show that the trajectory of an electromagnetic wave packet launched from the ground is a parabola. Note: one can use the same type of calculation to verify a sinusoidal trajectory through a slab light pipe in which n e ~ y 2 for both positive and negative y values. (2) The distance from the Earth to a pulsar can be estimated by observing the dispersion of the radio-frequency pulses as they cross the interstellar medium. a) Suppose the medium is a plasma of N electrons/cm 3 . What is the index of refraction n( ω ) where ω is the angular frequency of a wave? b) The pulsar emits a short pulse that contains a broad range of frequencies. We observe the pulse in a receiver that is tuned to a narrow band δω about an adjustable central frequency ω . We measure the time difference δ t between the arrival of two components of the pulse, centered at frequencies ω and ω + δω , where δω << ω . This can be done in a single receiver if the pulsar has a precise pulse rate {as is the case. Pulsars are the most accurately periodic macroscopic phenomenon ever observed}. case....
View Full Document

This note was uploaded on 05/14/2010 for the course EAD 234 taught by Professor Ncl during the Spring '10 term at École Normale Supérieure.

Page1 / 3

EAD234B_Homework2_2010 - EAD 234B: E&M Homework...

This preview shows document pages 1 - 2. Sign up to view the full document.

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