Issue 05
This article is about:
 Career Guidance
Interesting Science
 Real Life Application

Real Time News about Science
The Magic of Maglev
A brief review of magnets will help explain how maglev
(magnetic levitation) trains work. Every magnet has a
north pole and a south pole. Similar poles of two
magnets repel each other; opposite poles attract each
other. These principles govern the levitation of maglev
trains.
There are three components to the system:
1. A large electrical power source
2. Metal coils lining a guideway or track
3. Large guidance magnets attached to the underside
of the train
The big difference between a maglev train and a
conventional train is that maglev trains do not have an
engine -- at least not the kind of engine used to pull
typical train cars along steel tracks. The engine for
maglev trains is rather inconspicuous. Instead of using
fossil, the magnetic field created by the electrified coils
in the guide way walls and the track combine to propel
the train.
Permanent
magnets
are
always
magnetic.
Electromagnets are magnetic only when an electric
current flows through them. The north and south poles
of an electromagnet are related to the direction of the
current. If the direction of the current is reversed, the
poles are reversed.
In maglevs that levitate by magnetic repulsion, the train
lies over the guide way. Magnets on top of the guide
way are oriented to repel similar poles of magnets in the
bottom of the maglev. This pushes the train upward into
a hovering position. This system is designed for maglevs
that
contain
groups
of
extremely
powerful
superconducting electromagnets. These magnets use
less electricity than conventional electromagnets, but
they must be cooled to very low temperatures—from
−269 degrees Celsius to −196 degrees Celsius.
In maglevs that levitate by magnetic attraction, the
bottom of the train wraps around the guide way.
Levitation magnets on the underside of the guide way
are positioned to attract the opposite poles of magnets
on the wraparound section of the maglev. This raises
the train off the track. The magnets in the guide way
attract the wraparound section only strongly enough to
raise the train a few centimeters into a “floating” position.
The wraparound section does not touch the guide way.
(Imagine a C-shaped bracelet floating around your wrist
without touching it.)
To picture how a maglev train is propelled forward, think
of three bar magnets lined up on the floor. The magnet
in front is pulling with an attracting (opposite) magnetic
pole and the magnet in back is pushing with a repulsing
(similar) magnetic pole. The magnet in the middle
moves forward. A maglev's guide way has a long line of
electromagnets. These pull the train from the front and
push it from behind. The electromagnets are powered by
controlled alternating currents, so they can quickly
change their pull and push poles, and thus continually
propel the train forward.
Interesting Facts of Maglev Trains:
1. The first practical Maglev system was proposed and
published by us in 1966.
2. Japan has spent more than $2 billion in developing its
Maglev system, and Japan Railways’ Maglev vehicles
have clocked over 200,000 kilometers on the
Yamanashi guide way, carrying tens of thousands of
passengers.
3. The Shanghai maglev travels at a top speed of about
430 km (267 miles) per hour. One of the world's
fastest train, France's TGV, was clocked at a record
speed of 574.8 km per hour (357.2 miles per hour) in
April 2007.
4. On Sept. 22, 2006, a Transrapid test train in Emsland,
Germany had 29 people aboard during a test run
when it crashed into a repair car that had been
accidentally left on the track. The train was going at
least 120 mph (193 kph) at the time. Most passengers
were killed in the first fatal accident involving a maglev
train.
Glossary:
levitation: The state of rising and floating in the air in
apparent defiance of gravity.
repulsion: The tendency of particles or bodies of the
same electric charge or magnetic polarity to separate.
Article adapted from:
http://science.howstuffworks.com/transport/enginesequipment/maglev-train.htm
http://maglevtrains.weebly.com/cost--funfacts.htmlhttp://www.reuters.com/article/2008/01/15/idU
SSP21764
http://www.eduplace.com/science/hmxs/ps/mode2/cricke
t/sect7cc.shtml
Quiz Time!
Answer the question below to win simple but attractive prizes!
Submissions are to be dropped online through the website by
Friday, 5 pm, in the same week. The submission should include
your name and class. Each student can only make one
submission.
Q1 Currently, what is the fastest speed recorded for a
Maglev train?
Quiz URL: http://tinyurl.com/ScienceRead2017