- Equilibrium implies zero net force (translational equilibrium) and zero net torque or moment (rotational equilibrium). - Momentum of a system is conserved in the absence of external forces. Momentum of a single body is conserved only if the net force on it is zero. - Kinetic energy of an object is conserved only if no net work is done on it by non-conservative forces or if the system is isolated and interactions are perfectly elastic.
Consider the following statements: There is no net moment on a body which is in equilibrium. The momentum of a body is always conserved. The kinetic energy of an object is always conserved. Which of the statements given above is/are correct?
Asked in UPSC CDS 1 2018 · Topic: Mechanics (Newton's Laws of Motion and their applications)
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