Download 2-1 magnetism

2-1 MAGNETISM
-MAGNETISM IS THE FORCE EXERTED BETWEEN CHARGED MATERIALS
THAT EITHER PULLS THEM TOGETHER OR PUSHES THEM APART. THE
AREAS WHERE THE FORCE IS STRONGEST IS CALLED THE POLES, WHICH
ARE AT THE ENDS OF THE MAGNET.
-WHEN 2 MAGNETS COME TOGETHER THEY EXERT A FORCE ON EACH
OTHER. WEATHER IT WILL ATTRACT OR REPELL DEPENDS ON HOW THEY
ARE LINED UP.
-POLES ARE ALWAYS IN PAIRS, A NORTH AND A SOUTH. EVEN IF A
MAGNET IS CUT IN HALF, IT RETAINS BOTH POLES.
-A MAGNETIC FIELD IS THE AREA WHERE THE MAGNETIC FORCE IS
EXERTED OVER.
-SOME MATERIALS CAN BE MAGNETIZED AND OTHERS ARE NOT.
HIGHLY MAGNETIC MATERIALS ARE CALLED “FERROMAGNETIC
MATERIALS”. WHY WOULD IT HAVE THIS NAME?
HINT: CHEMISTRY- NAMES OF ELEMENTS (LATIN)
***FERRUM IS THE LATIN NAME OF IRON***
-FM ‘S ARE STRONGLY ATTRACTED TO MAGNETS AND CAN ALSO BE MADE
INTO THEM. THEY DO HOWEVER LOSE THEIR MAGNETISM EASILY.
-THE ATOMIC STRUCTURE DEFINES THE MAGNETIC PROPERTIES OF THE
OBJECT. THE AREA CALLED THE MAGNETIC DOMAIN IS WHERE THE
MAGNETIC FIELDS OF ATOMS LINE UP TOGETHER. THIS DOMAIN CAN BE
ALTERED IN FM’S TO CREATE MAGNETS. EXAMPLE = PAPER CLIPS
-IN UNMAGNETIZED MATERIAL, THE DOMAINS ARE ALL POINTING IN
DIFFERENT DIRECTIONS. BECAUSE OF THIS THE CHARGES CANCEL OUT
AND LEAVE NO MAGNETIC FORCE.
-MAGNETISM IN AN OBJECT CAN BE LOST BY STRIKING, DROPPING, AND
HEATING. IF THIS HAPPENS, THE DOMAINS ARE MOVED AROUND OUT OF
ALIGNMENT.
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2-2 THE EARTH AS A MAGNET
-THE EARTH GIVES OFF A MAGNETIC FORCE. IT HAS MAGNETIC POLES
JUST LIKE A MAGNET WOULD HAVE. THE MAGNETIC POLES ARE AT AN
ANGLE AND NOT STRAIGHT UP AND DOWN.(P.53 PICTURE)
-LIKE A MAGNET, THE EARTH HAS A MAGNETIC FIELD THAT IS
STRONGEST AT THE POLES. IN MOLEN ROCKS, THEIR PARTICLE LINE UP
WITH THE MAGNETIC POLES. THIS GIVES US A PERMANENT RECORD OF
THE DIRECTION OF THE MAGNETIC POLES. OVER TIME, SCIENTISTS HAVE
FOUND HOW TO DETECT THESE RECORDS AND HAVE FOUND THAT THE
MAGNETIC POLES OF THE EARTH HAVE REVERSED MANY TIMES.
-IN A COMPASS, WHERE THE NEEDLE IS MAGNETIZED, THE EARTH EXERTS
A FORCE ON IT. KNOWING THE FORCES OF MAGNETISM…IS THE COMPASS
NEEDLE ACTUALLY POINTING NORTH?
-THERE ARE OTHER THINGS IN THE GALAXY THAT GIVE OFF A MAGNETIC
FORCE, SUCH AS OTHER PLANETS. FOR EXAMPLE, JUPITER HAS A FIELD 13
TIMES STRONGER THAN US!
-SUNSPOTS ARE DARK AREAS ON THE SUN, WHICH REPRESENT AREAS
WHERE MAGNETIC LINES OF FORCE COME THROUGH THE SUN’S SURFACE.
BECAUSE THEY ARE MAGNETIC, THEY WILL ALWAYS OCCUR IN PAIRS,
LIKE MAGNETIC POLES DO. EVERY 11 YEARS THE SUN’S MAGNETIC FIELD
REVERSES AND THE POLES SWITCH.
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2-3 MAGNETISM IN ACTION
-A MAGNETIC FIELD WILL ONLY EXERT A FORCE ON A CHARGED
PARTICLE IF IT IS MOVING AT AN ANGLE TO IT. IF THE CHARGED
PARTICLE IS MOVING IN THE SAME DIRECTION, A MAGNETIC FIELD WILL
EXERT NO FORCE ON IT.
-THE MAGNETOSPHERE IS THE AREA WHERE THE MAGNETIC FIELD OF THE
EARTH IS FOUND. THIS MAGNETOSPHERE IS SHAPED INTO A LONG TAIL
ON THE OPPOSITE SIDE OF THE SUN BECAUSE OF SOLAR WINDS. SOLAR
WINDS ARE CHARGED PARTICLES COMING TOWARDS THE EARTH.
-THE EARTH’S MAGNETIC FIELD DEFLECTS MOST OF THE CHARGED
PARTICLES FROM THE SUN. IF THE PARTICLES DO GET THROUGH, THEY
GET TRAPPED IN THE MAGNETIC FIELD LINES OF THE EARTH AND REMAIN
THERE, TRAVELLING FROM POLE TO POLE.
-WHEN THESE CHARGED PARTICLES GET CLOSE TO THE EARTH, THEY
CAUSE A GLOWING EFFECT. THIS GLOWING AREA IS CALLED AN AURORA.
THE AURORA’S OF THE EARTH ARE FOUND NEAR THE POLES. THE
AURORA IN THE NORTH IS CALLED THE AURORA BOREALIS (NORTHERN
LIGHTS), WHILE THE AURORA IN THE SOUTH IS CALLED THE AURORA
AUSTRALIS.
-RADIO WAVES ARE PRODUCED BY PARTICLES TRAPPED IN MAGNETIC
FIELDS. WE CAN USE THESE RADIO WAVES TO LEARN ABOUT THE
UNIVERSE.
-HUGE AMOUNTS OF ENERGY WE CAN USE CAN BE FOUND BY FUSING TO
ATOMS TOGETHER. UNDERSTANDING CHARGED PARTICLES AND THEIR
MAGNETIC FORCES MAY HELP US TO ONE DAY FIND THIS SOLUTION.
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