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Question
Explain balancing or mechanical equilibrium. The linear velocity of a rotating fan as a whole is generally zero. Is it in mechanical equilibrium? Justify your answer.
Solution
- The state in which the momentum of a system is constant in the absence of an external unbalanced force is called mechanical equilibrium.
- A particle is said to be in mechanical equilibrium if no net force is acting upon it.
- In the case of a system of bodies to be in mechanical equilibrium, the net force acting on any part of the system should be zero i.e., the velocity or linear momentum of all parts of the system must be constant or zero. There should be no acceleration in any part of the system.
- Mathematically, for a system in mechanical equilibrium, `sumvec"F"` = 0.
- In the case of a rotating fan, if the linear velocity is zero, then the linear momentum is zero. That means there is no net force acting on the fan. Hence, the fan is in mechanical equilibrium.
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