The mechanical universe - 34 - magnetism .

Lesson 34: Magnets William Gilbert, personal physician by appointment to her Majesty Queen Elizabeth I of England, discovered that the earth behaves like a giant magnet. Magnetism as a natural phenomenon, the behavior of magnetic materials, and the motion of charged particles in a magnetic field.

Instructional Objectives

* Be able to calculate the magnetic force on a current element and on a moving charge in a given magnetic field.
* Know the definition of torque and potential energy for a magnetic dipole.
* Be able to explain the concept of domains in ferromagnetic materials.
* Be able to use the definition of magnetic flux and discuss the significance of the result that the net magnetic flux out of a closed surface is zero.
* Be able to calculate the magnetic moment of a current loop and the torque exerted on a current loop in a magnetic field.
* Be able to discuss the magnetism of the Earth.

This series helps teachers demystify physics by showing students what it looks like. Field trips to hot-air balloon events, symphony concerts, bicycle shops, and other locales make complex concepts more accessible. Inventive computer graphics illustrate abstract concepts such as time, force, and capacitance, while historical reenactments of the studies of Newton, Leibniz, Maxwell, and others trace the evolution of theories.

The Mechanical Universe helps meet different students' needs, from the basic requirements of liberal arts students to the rigorous demands of science and engineering majors. This series is also valuable for teacher professional development. Produced by the California Institute of Technology and Intelecom.


Caltech: The Mechanical Universe - 34 - Magnetism.

Dan Gilbert: Why are we happy? Why aren't we happy?

In this memorable talk, Dan Gilbert demonstrates just how poor we humans are at predicting (or understanding) what will make us happy. Gilbert is a psychology professor at Harvard, and author of "Stumbling on Happiness".

Dan Gilbert: Why are we happy? Why aren't we happy?

Dr Who - Adventures in time and space.

A documentary on the complete history of Doctor Who, originally broadcast as part of the BBC's "Doctor Who Night" in 1999.

Here is a list of all who played Doctor Who;

# First Doctor, played by William Hartnell (1963–1966)
# Second Doctor, played by Patrick Troughton (1966–1969)
# Third Doctor, played by Jon Pertwee (1970–1974)
# Fourth Doctor, played by Tom Baker (1974–1981)
# Fifth Doctor, played by Peter Davison (1981–1984)
# Sixth Doctor, played by Colin Baker (1984–1986)
# Seventh Doctor, played by Sylvester McCoy (1987–1989, 1996)
# Eighth Doctor, played by Paul McGann (1996)
# Ninth Doctor, played by Christopher Eccleston (2005)
# Tenth Doctor, played by David Tennant (2005–)

Other actors have also played the Doctor, though rarely more than once.

Adventures in time and space.

Race: The power of an illusion.

Race is one topic where we all think we're experts. Yet ask 10 people to define race or name "the races," and you're likely to get 10 different answers. Few issues are characterized by more contradictory assumptions and myths, each voiced with absolute certainty.

We felt it was important to go back to first principles and ask, What is this thing called "race?" - a question so basic it is rarely raised. What we discovered is that most of our common assumptions about race - for instance, that the world's people can be divided biologically along racial lines - are wrong. Yet the consequences of racism are very real. (Larry Adelman)

Race: The power of an illusion.