Which of the following pairs does not have identical dimensions ?
Correct answer: D. Mass and moment of inertia
- A. Torque and energy
- B. Momentum and impulse
- C. Energy and work
- D. Mass and moment of inertia
Explanation
Torque and energy both have dimensions ML²T^-2, momentum and impulse both have dimensions MLT^-1, and energy and work both have dimensions ML²T^-2. Mass has dimension M, whereas moment of inertia has dimension ML² because it includes mass multiplied by distance squared. Option a is a tempting alternative because torque and energy have the same dimensions but different physical meanings.
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