A body having moment of inertia of 30 kg m² is rotating at 210 RPM and mashes with another body at rest having M.I. of 40 kg m². The resultant speed after meshing will be

Solution: Given,
Moment of inertia of first body (I1) = 30 kg m^2
Rotational speed of first body (ω1) = 210 RPM
Moment of inertia of second body at rest (I2) = 40 kg m^2
To find: Resultant speed after meshing Formula:
Conservation of Angular Momentum: I1ω1 = (I1+I2)ω2
where, ω2 = Resultant speed after meshing
Calculation: Substituting the given values in the formula, we get
30 × 210 = (30 + 40) × ω2 ω2 = (30 × 210) / (30 + 40) ω2 = 90 RPM
Therefore, the resultant speed after meshing is 90 RPM.

Wrong answer 157.5 right answer

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