Practice question

Given: A 3 kg mass moving at 12 m/s collides elastically with an identical stationary mass. What is the speed of the first mass after collision? These values define the system as per NCERT data. Formula: For equal masses in elastic collision, v_{1f = 0 m/s (first mass stops).. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Substituting values like 1.2 × 10⁻⁵, 236 J kg⁻¹ K⁻¹, CH₃CH₂NH₂ etc. into the formula and simplifying step by step. 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.