Question

In: Physics

In the figure, two particles, each with mass m = 0.77 kg, are fastened to each...

In the figure, two particles, each with mass m = 0.77 kg, are fastened to each other, and to a rotation axis at O, by two thin rods, each with length d = 5.2 cm and mass M = 1.0 kg. The combination rotates around the rotation axis with angular speed ? = 0.32 rad/s. Measured about O, what is the combination's (a) rotational inertia and (b) kinetic energy?

Solutions

Expert Solution

a)

Moment of inertia of rod between the two particles of masses and , about its ceter of mass is

Moment of inertia of rod between the two particles of masses   and about the axis of rotation O is

Moment of inertia of rod between first particle of mass and axis of rotation O, about O is

Moment of inertia of first particle of mass about the axis or rotation O is

Moment of inertia of second particle of mass about the axis of rotation O is

Total moment of inertia of the two rods and two particles about the axis of rotation O is

Moment of inertia of the combination is  

b)

Kinetic energy of the combination is


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