Effective mass may refer to:
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Effective mass (solid-state physics)
In solid state physics, a particle's effective mass (often denoted m^*) is the mass that it ''seems'' to have when responding to forces, or the mass that it seems to have when interacting with other identical particles in a thermal distribution. ...
, a property of an excitation in a crystal analogous to the mass of a free particle
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Effective mass (spring–mass system)
In a real spring–mass system, the spring has a non-negligible mass m. Since not all of the spring's length moves at the same velocity v as the suspended mass M, its kinetic energy is not equal to \tfrac m v^2. As such, m cannot be simply added t ...
See also
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Reduced mass
In physics, the reduced mass is the "effective" Mass#Inertial mass, inertial mass appearing in the two-body problem of Newtonian mechanics. It is a quantity which allows the two-body problem to be solved as if it were a one-body problem. Note, how ...
, used to simplify a two-body problem in terms of a one-body problem
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