An object consists of a rod (of length 3.0 m and negligible moment of inertia)to which four small 2.0-kg masses are attached,one at each end and one at each point on the rod 1.0 m from each end.(The masses are one meter apart. )The moment of inertia of this object about an axis perpendicular to the rod and through one of the inner masses: A)is 72 kg*m². B)is 12 kg*m². C)is 4 kg*m². D)cannot be uniquely determined until it is stated which inner mass the axis goes through.

Question

Quizplus · Accepted Answer

The moment of inertia is calculated using I = Σmr². For the axis through one of the inner masses, the distances are 0 m, 1 m, 1 m, and 2 m. Thus, I = 2(0)² + 2(1)² + 2(1)² + 2(2)² = 0 + 2 + 2 + 8 = 12 kg·m².

An Object Consists of a Rod (Of Length 3