Two point masses m₁ and m₂ are attached to the ends of a light rod of length ℓ. Find the moment of inertia about a transverse axis through their centre of mass.
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Two point masses m₁ and m₂ are attached to the ends of a light rod of length ℓ. Find the moment of inertia about a transverse axis through their centre of mass.

G1 Physics · Accepted Answer

Step 1: Distances of m₁ and m₂ from COM are m₂ℓ/(m₁+m₂) and m₁ℓ/(m₁+m₂). Step 2: Substitution into I=m₁r₁²+m₂r₂² yields I=m₁m₂ℓ²/(m₁+m₂). Final answer: A — m₁m₂ℓ²/(m₁+m₂).