GATE 2020 ME (ME1) – Question 30
A flywheel keeps an engine’s rotational speed between 100 and 110 rad/s. Energy fluctuation between these speeds is 1.05 kJ. Find its moment of inertia (kg·m²), to two decimals.
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Show answer and explanation
Correct answer: .98 to 1.02
Explanation
Rotational energy is Iω²/2. Therefore $1050=I(110^2-100^2)/2=1050I$. Solving gives **I=1.00 kg·m²**. Convert kJ to J before substituting angular speeds in rad/s.