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Formula Reduced mass of a two-body system

Formula
Formula: Reduced mass of a two-body system

Reduced mass

Unit
Effective mass is used to reduce a two-body problem (e.g., the motion of the Earth around the Sun about the common center of mass) to a one-body problem.

If \( m_1 ~\gg~ m_2 \) holds, then the formula for the reduced mass can be approximated by the mass of the lighter body: \( \mu ~\approx~ m_2 \).

Mass

Unit
This can be for example the mass of the earth moving around a center of mass C.M. of the earth and sun.

Mass

Unit
This can be, for example, the mass of the Sun rotating around a center of mass of the Earth-Sun system.