A system of three point particles of equal masses 45 gm are initially connected by three rods of negligible mass to an axis of rotation perpendicular to the plane of the particles as shown in the figure-1.(a) What is the moment of inertia of the system of three particles? (b) If the massless rods are replaced by three rods of equal masses of 65 gm keeping their lengths unchanged, what is the moment of inertia of the system now? (c) If the systems rotate at 4.75 rev/s, what are the systems rotational kinetic energies?
Rigid Body
A rigid body is an object which does not change its shape or undergo any significant deformation due to an external force or movement. Mathematically speaking, the distance between any two points inside the body doesn't change in any situation.
Rigid Body Dynamics
Rigid bodies are defined as inelastic shapes with negligible deformation, giving them an unchanging center of mass. It is also generally assumed that the mass of a rigid body is uniformly distributed. This property of rigid bodies comes in handy when we deal with concepts like momentum, angular momentum, force and torque. The study of these properties – viz., force, torque, momentum, and angular momentum – of a rigid body, is collectively known as rigid body dynamics (RBD).
A system of three point particles of equal masses 45 gm are initially connected by three rods of negligible mass to an axis of rotation perpendicular to the plane of the particles as shown in the figure-1.(a) What is the moment of inertia of the system of three particles?
(b) If the massless rods are replaced by three rods of equal masses of 65 gm keeping
their lengths unchanged, what is the moment of inertia of the system now?
(c) If the systems rotate at 4.75 rev/s, what are the systems rotational kinetic
energies?
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