Practice question

Given: A 2 kg ball moving at 6 m/s collides elastically with a stationary 4 kg ball. What is the speed of the 4 kg ball after collision? These values define the system as per NCERT data. Formula: For elastic collision: v_{2f = 2 m_1/m_1 + m_2 v_{1i = 2 × 2/2 + 4 × 6 = 4/6 × 6 = 4 m/s .. 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.