Magnetic Earth

Synopsis

Discusses the invisible force field of magnetism which surrounds the earth. Sensitive compasses were used to map the intensity and direction of the magnetic field at the earth’s surface, and recently satellits have extended this data. Molten lava from volcanoes cools to ‘freeze’ the magnetic field of the time, providing a record of magnetic history. Considers two models for the origin of the earth’s magnetic field - a constructed Victorian globe (Wildes’s magnetarium) and a modern self-excited dynamo.

Series

Science Foundation Course, A: Course S102

Language

English

Country

Great Britain

Medium

Video; Videocassette. Standard formats. col. 25 min.

Year of production

1987

Availability

Off-air recording licence
Sale; 1998 sale: £145.00 (+VAT +p&p)

Subjects

Physics

Keywords

earth; magnetism

Credits

Producer

Tony Jolly

Production Company

Name

BBC Open University Productions

Distributor

Name

Open University Worldwide

Web

http://www.ouw.co.uk External site opens in new window

Phone

+44 (0) 1908 274066

Address

Walton Hall
Milton Keynes
MK7 6AA

Notes

NB. As of May 2016 Open University Worldwide are no longer distributing DVDs. They have posted this message on their website: ‘Unfortunately Open University Worldwide Limited has decided that product sales are no longer viable given the reduced funding to Higher Education institutions and diminishing demand for the products we have traditionally stocked. At present the Open University Students Association (OUSA) will continue to sell the "Good Study Guide", and we are in discussion with other possible distributors to continue to make The Open University’s products available for purchase. As soon as we have any information on other channels of distribution we will update this notice’. Some products are still available via second hand dealers on Amazon.co.uk