1. A bar magnet is broken in half. Each half is broken in half again
... 2. Maxwell's great contribution to electromagnetic theory was his hypothesis that:
A) work is required to move a magnetic pole through a closed path surrounding a current
B) a time-varying electric flux acts as a current for purposes of producing a magnetic
C) the speed of light could be deter ...
... and σ = 3 x 10 7 mhos/m, calculate the skin depth at 10 8 Hz
Q. 11 If in a time invariant field, the magnetic field associated with a plane
electromagnetic wave has only z – component which is expressed as
then obtain an expression for current density
Q. 12 A plane electromagnetic wave pr ...
modello di descrizione delle singole attivita`formative
... conductors; electric potential and potential energy; capacitors; energy density of the electric
field; D field. Electric current: electromotive force; Ohm, Joule, Kirchhoff’s laws. Magnetism:
magnets and magnetic dipoles; Lorenz force; Ampère’s equivalence principle; 1st and 2nd
Laplace formula; Amp ...
Forces on Moving Charges in Magnetic Fields Standards
... Students should understand the force experienced by a charged particle in a
magnetic field, so they can:
1) Calculate the magnitude and direction of the force in terms of q, v, and B and
explain why the magnetic force can perform no work.
2) Deduce the direction of a magnetic field from information ...
... motion of electric charges, i.e., electric
current. The magnetic field causes the
magnetic force associated with magnets.
... Morley looked and looked, and decided it wasn’t
there. How do waves travel???
Electricity and magnetism are “relative”:
Whether charges move or not depends on which
frame we use…
This was how Einstein began thinking
about his “theory of special
We’ll leave that theory for later…maybe.
... What causes our Magnetic Field?
The Dynamo Theory:
►Rotation of the earth causes liquid
rock in outer core to spin
►Moving electrons from the iron &
nickel creates an electric current
►Electric currents produce magnet
fields (Faraday’s Law)
An electromagnetic field (also EMF or EM field) is a physical field produced by electrically charged objects. It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space and describes the electromagnetic interaction. It is one of the four fundamental forces of nature (the others are gravitation, weak interaction and strong interaction).The field can be viewed as the combination of an electric field and a magnetic field. The electric field is produced by stationary charges, and the magnetic field by moving charges (currents); these two are often described as the sources of the field. The way in which charges and currents interact with the electromagnetic field is described by Maxwell's equations and the Lorentz force law.From a classical perspective in the history of electromagnetism, the electromagnetic field can be regarded as a smooth, continuous field, propagated in a wavelike manner; whereas from the perspective of quantum field theory, the field is seen as quantized, being composed of individual particles.