A 8kg block is pushed with 40N over 6m on a frictionless surface, starting from 2m/s. What is its final speed?
Initial Ki=12×8×22=16J. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 8 m/s. This satisfies dimensional consistency and physical conditions given, so option B is scientifically correct.
Ref: NCERT Class 11 Physics > Chapter 6: Work, Energy and Power > Topic: Laws of Motion and Energy Conservation