5H10.20 - Oersted's Effect

Code Number:
Demo Title:
Oersted's Effect
Forces & Fields due to Induced Currents
Area of Study:
Electricity & Magnetism
Weather Vane Compass Under a Wire and 6 Volt DC/30 Amp Power Supply.

Turn on the supply and the compass will line up perpendicular to the wire. There is also a smaller overhead model of this to be used with the same power supply.

The Pasco dip needle/Oersted's law apparatus is a compact easy to use unit.  Instructions for this unit are in the 5H10.20 pdf file folder.

  • Ponn Maheswaranathan, "An Experiment to Verify the Current Dependence of Ampere's Law for a "Long" Straight Current-Carrying Conductor", TPT, Vol. 58, #8, Nov. 2020, p. 581.
  • Thomas B. Greenslade Jr, "Apparatus Named After Our Academic Ancestors-II", TPT, Vol. 49, # 1, January 2011, p. 28.
  • Keith Thompson, "The Current in a Wire", TPT, Vol. 47, # 2, Feb.  2009, p. 103.
  • Jeffrey Phillips, Jeff Sanny, "Phillips and Sanny's Response", TPT, Vol. 46, # 5, May 2008, p. 262.
  • Arthur Hovey, "The Biot-Savart Law -- Another Approach", TPT, Vol. 46, May 2008, p. 261.
  • Jeffrey A. Phillips, Jeff Sanny, "The Biot-Savart Law: From Infinitesimal to Infinite", TPT, Vol. 46, # 1, Jan. 2008, p. 44.
  • F.M. Gibson and Iain MacInnes.  "Symmetry in Electromagnetism - A New Magnetic Needle",  TPT, Vol. 38, # 5, p. 316, May 2000.
  • Paul Robinson, "Oersteds in the Hydrolytic Plant", TPT, Vol. 32, # 1, Jan. 1994, p. 57.
  • Paul G. Menz, "Correction", TPT, Vol. 32, # 2, Feb. 1994, p. 68.
  • Robert H. Romer,  "Oersted on the Subway",  TPT, Vol. 31, # 2, p.  92, February 1993.  
  • Sam J. Cipolla, "The Oersted Effect on the Overhead", TPT, Vol. 13, # 8, Nov. 1975, p. 475, reprinted in TPT, Vol. 40, # 9, p. 47, Jan. 2002.
  • Francis S. Lestingi, "Oersted Overhead ", TPT, Vol. 8, # 3, March 1970, p. 140.
  • Thomas B. Greenslade, Jr., "Oersted's Law Demonstrator", AJP, Vol. 89, #12, Dec. 2021, p. 1151.
  • B. J. Pernick,  "Simultaneous Measurement of the Straight Wire and the Earth's B Field", AJP, p. 90, Vol. 57, # 1, January 1989.
  • Ei-8:  Freier and Anderson,  A Demonstration Handbook for Physics.
  • B-105:  "Wire and Compass Needle",  DICK and RAE Physics Demo Notebook.
  • E-121, 122:  Richard Manliffe Sutton, Demonstration Experiments in Physics.
  • George M. Hopkins', Experimental Science, Volume Two, p. 113.
  • Yaakov Kraftmakher, "1.8, Oersted's Great Discovery", Experiments and Demonstrations in Physics, ISBN 981-256-602-3, p. 28.
  • Bill Franklin, "Abstract: Compass and Wire Holder for Detecting Currents",  2005 Apparatus Competition, Salt Lake City, UT.
  • Grant Mellor, "The Great Magnetic Discovery", Flying Tinsel, 1993, p. 96-99.
  • Rudolf F. Graf, "Relating Electricity with Magnetism (Electromagnetism)", Safe and Simple Electrical Experiments, p.86.
  • Joseph Frick, "# 303 - Magnetic Effects of the Current", Physical Technics: Or Practical Instructions for Making Experiments in Physics and the Construction of Physical Apparatus with the Most Limmited Means, p. 351.

Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.