PHYS/GEOL 406 Homework
RU Links
  Radford University
  Department of Physics
  RU Planetarium
  RUSMART pages (weather)

Spring 2015 Classes & Info
  PHYS 308
  PHYS 309
  My daily schedule
  My C.V.

Summer jobs/internships
  NSF REU Program (list of REU sites)

Other links
  The Nucleus (resources for
   physics/astronomy undergrads)
  Pre-Health information
   pics from the north pole trip
   the picture from the trip
  Simple 2-liter water rocket
  American Institute of Physics

   Homework #11: Due Friday, April 17, by 5:00pm.


  • Section 7.2.1 to 7.2.3
  • Guess what is helpful with Earth's magnetic field--this is. So is this.
  1. You are at a place on Earth where HE = 12,628 nT; i = 77° 9' (downward); and XE = 5,133 nT. Compute the four remaining magnetic elements (declination 'd', YE, ZE and JE) of this location from the data given.
  2. Consider this magnetic profile taken in a north-south line over a spherical body that has been magnetized by Earth's field. (a) Calculate the approximate depth to the center of this object. (b) Is the location y=(-)10m the southern or northern end of this profile? Explain your reasoning. Hint: Perhaps a drawing of the magnetic field of this anomaly would be helpful here.
  3. Consider this magnetic profile of a magnetized body. Consider this to be a single-lobed feature (i.e. that blue area to the north is due to something other than this body). (a) Draw a magnetic transect profile across this body along a north-south line. (b) Calculate the depth to the center of this body.
  4. A magnetized body is buried with its north magnetic pole pointing straight down. Assume this body is in the northern hemisphere at the general latitude of Radford. (a) Draw the magnetic field lines due to Earth and due to this body as they interact above the surface. (b) Use "+" and "-" and "NC" for "add to (the total mag. field measurement)" and "subtract from" and "no change" as I did in class and label the places where these labels apply along a fixed height above the surface. (c) Make a rough graph of the magnetic anomaly (total field) as indicated by your labels.
  5. Calculate the horizontal magnetic field gradients of Earth's magnetic field here at Radford (37.14°N, 80.55°W) right now. This site might be helpful.

That's all for homework #11.