Practice question

Given: A 4 kg mass is lifted 6 m in 3 s at constant speed. What is the power? (Take g = 10 m/s² ) These values define the system as per NCERT data. Formula: Work W = mgh = 4 × 10 × 6 = 240 J. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Power P = W/t = 240/3 = 80 W . Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kg⁻¹ K⁻¹, m/s², 10⁻⁵ are properly used as per NCERT.