# The Four Fundamental Forces

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What is the fastest speed which anything can
move?
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What is the fastest speed which anything can
move?
In a vacuum nothing travels faster than the
speed of light.
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Does the speed of light change for observers
depending on their position or motion?
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Does the speed of light change for observers
depending on their position or motion?
The speed of light is the same for all
observers no matter how they or the light
source are moving.
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The Strong Nuclear Force
The Electromagnetic Force
The Weak Nuclear Force
Gravity
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The strongest of the four forces.
Acts inside the nucleus.
Attractive force between protons and
neutrons that holds the nuclei of atoms
together.
Very short range force.
&gt; Acts over a distance of 10-15 m which is
the diameter of a medium size nucleus.
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2nd strongest force.
Strong force is 137 times stronger.
The electromagnetic force holds atoms and
molecules together.
Responsible for all forces experienced with
the exception of gravity. (All contact forces
are electromagnetic in nature).
Range is infinite (strength obeys inverse
square law.)
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3rd strongest force.
Strong force is 1,000,000 times stronger.
neutrino interactions.
VERY short range force.
&gt; Acts over a distance of 10-18 m which is
0.1 % of the diameter of a proton.
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Weakest of the four forces. Strong force
is1.67 x 1038 times stronger.
Responsible for the structure of the universe
on the larger scale.
Range is infinite (strength obeys inverse
square law.)
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STRONG :Glues protons together, protons must
be very close, strongest of all forces, limited
range
WEAK : responsible for radioactive decay;
neutron decay
ELECTROMAGNETIC : electrons kept in orbit.
Opposites attract; holds atom together
GRAVITY :the weakest of the forces four
fundamental forces, yet it, all objects are
influenced by it, at an infinite distance
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