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RADIOACTIVITY
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All
the elements having atomic number greater than 82 emit invisible radiation
all the time. The phenomenon of emission of these powerful rays is called
"Natural Radioactivity" and the element that emits such
rays is called "Radio Active Elements".
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TYPES
OF RADIO ACTIVE RAYS
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There
are three types of radioactive rays:
a-Rays
b-RAYS
g-RAYS |
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PROPERTIES
OF a-RAYS
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NATURE: a - rays consist of α particle.
Each α particle consists of 2He4 nucleus. |
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CHARGE: a - particle carry positive charge.
MASS: Mass of each a - particle is 4 times
that of a proton or H-atom. |
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IONIZATION: Ionization power of a - rays
is very high.
PENETRATION POWER: Penetration power of a - rays
is very small.
FLUORESCENCE: a - rays produce fluorescence
in different substances.
EFFECT ON HUMAN BODY: a - rays produce burn
and source on human body.
ARTIFICIAL RADIO ACTIVITY: a - rays can produce
artificial radioactivity is certain nuclei.
IONIZATION CAPABILITY : They have strong ionizing power because they
remove electrons from the atoms of gas through which
they pass.
VELOCITY: Their velocity range is 3 x 107 m/s to 3 x 106
m/s. |
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PROPERTIES
OF b-RAYS
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NATURE: b - rays consist of fast moving electrons.
CHARGE: b - rays have negative charge.
VELOCITY: Velocity of b - rays is from 9
x 107 m/sec to 27 x 107 m/sec.
EFFECT ON PHOTO GRAPHIC PLATE: b - rays affect
the photo graphic plate.
IONIZTION POWER: Ionization power of b - rays
is very small.
KINETIC ENERGY: Kinetic energy of b - rays
is less than that of a - rays.
FLUORESCENCE: b - rays produce fluorescence
in different substance. |
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PROPERTIES
OF g-RAYS
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NATURE: g - rays
are electromagnetic radiations.
CHARGE: g - rays are no charge.
VELOCITY: g - rays travel with the velocity
of light that is 3 x 108 m/sec.
PENETRATION POWER: Penetration power of g
- rays is very large. It is about hundred times larger than
that of b -rays.
FLUORESCENCE: g - rays produce feeble fluorescence
When incident on screen coated with barium platino
cyanide. |
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Contact
us:
info@citycollegiate.com |
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