WAEC Physics 2024 Paper

Concept:The dimensions of a physical quantity are expressed in terms of mass $M$, length $L$, and time $T$.Explanation:Stress has the same dimensions as pressure: $[ML^{-1}T^{-2}]$.Strain is dimensionless because it is a ratio of lengths: $[M^0L^0T^0]$.Therefore, Stress $\times$ Strain has dimensions $[ML^{-1}T^{-2}]$.Pressure has dimensions $[ML^{-1}T^{-2}]$.$\frac{\text{stress}}{\text{strain}}$ also has dimensions $[ML^{-1}T^{-2}]$, since strain is dimensionless.Torque $=$ Force $\times$ perpendicular distance, so its dimensions are $[MLT^{-2}][L] = [ML^2T^{-2}]$.Thus, Torque has a dimension different from the other three.Answer:D. Torque