MCQs on Units and Dimensions (With Solutions)-Part I
Q1. Which of the following pairs have the same dimensions? A. Energy and Torque B. Power and Force C. Momentum and Impulse D. Pressure and Stress Answer: C. Momentum and Impulse Solution: Momentum = mv = [M][L] [T −1 ] Impulse = F ⋅ t= [M][L] [T −1 ] Hence, same dimensions. Q2. Which of the following quantities is dimensionally different from the others? A. Work B. Energy C. Torque D. Power Answer: D. Power Solution: Work, Energy, Torque: [ML 2 T −2 ] Power = [ML 2 T −3 ] → Different Q3. The dimensional formula for Planck's constant is: A. [ML 2 T −1 ] B. [MLT −2 ] C. [ML 2 T −2 ] D. [ML 2 T −3 ] Answer: A. [ML 2 T −1 ] Solution: E=hν ⇒ h=E/ν h=[ML 2 T −2 ]/[T −1 ] =[ML 2 T −1 ] Q4. Which physical quantity has the same dimensions as that of pressure? A. Energy B. Force C. Stress D. Torque Answer: C. Stress Solution: Both Pressure and Stress = [ML −1 T −2 ] Q5. If the accelerati...