Physics education research, electronic materials, and the musings of Christopher Moore, Ph.D.
Physics education research, electronic materials, and the musings of Christopher Moore, Ph.D.
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Greeting every one.
In Duffing equation, the damping coeffecient usually assume possitive values (<<1). However, at certain cases, the damping coeffecient may asume negative values.
Can any one explain the meaning of positive and negative damping in Duffing equation as well as in real physical systems.
Further, in modelling the nonlinear response of a nonlinear material driven by optical laser source using Duffing equation, what type of damping we have in this case.
any contribution is appreciated
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Damping coefficient is always positive.
Damping coefficient is obtain from simplification of drag force.
scalar value of drag force is F= C_{1}v+C_{2}v^{2}
The first term is viscous term and second term is pressure term. In case of oscillation, second term (pressure term) is always negligible. So scalar value of drag force for oscillation is F=C_{1}v , C_{1} is damping coefficient. The direction of drag force is always in opposite direction of moving object. Sign minus is meaning that force is acting in opposite direction of moving object.
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Damping coefficient is always positive.
Damping coefficient is obtain from simplification of drag force.
scalar value of drag force is F=
The first term is viscous term and second term is pressure term. In case of oscillation, second term (pressure term) is always negligible. So scalar value of drag force for oscillation is F= ,
is damping coefficient. The direction of drag force is always in opposite direction of moving object. Sign minus is meaning that force is acting in opposite direction of moving object.
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