Practice question

Given: In a new system, the unit of mass is 2 kg, length is 0.5 m, and time is 3 s . What is the value of 1 J ( kg m² s^{-2 ) in this system? These values define the system as per NCERT data. Formula: 1 J = 1 kg m² s^{-2. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: New units: kg = 2 α, m = 0.5 β, s = 3 γ . 1 J = (2 α) (0.5 β)² (3 γ)^{-2 = 2 × 0.25 × 1/9 = 0.5/9 = 0.0556 α β² γ^{-2 . 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.