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Question
What do you mean by dynamic and static equilibrium? Give one example of each.
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Solution
When the body remains in the state of rest under the influence of applied forces, it is in static equilibrium and if it remains in the state of uniform motion, it is in dynamic equilibrium.
For example: In a beam balance when the beam is balanced in the horizontal position, the clockwise and anti-clockwise moments balance each other and the beam has no rotational motion i.e., it is in static equilibrium.
A body moving with uniform velocity in a straight line over a frictionless surface is in dynamic equilibrium.
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