A 4kg block slides down a frictionless incline from a height of 3m. What is its speed at the bottom? (Take g\=10m/s2)
Potential energy mgh=4×10×3=120J. As per NCERT, applying relevant law/formula with correct units and sign convention leads to 7 m/s. This satisfies dimensional consistency and physical conditions given, so option A is scientifically correct.
Ref: NCERT Class 11 Physics > Chapter 6: Work, Energy and Power > Topic: Work, Energy and Power - Work-Energy Theorem