Practice question

Given: Minimum speed to escape from 2 R_E from Earth’s nter is? ( g = 9.8 m/s², R_E = 6.4 × 10⁶ m ) These values define the system as per NCERT data. Formula: v_e = sqrt2 g R_E²/2 R_E = sqrtg R_E. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: v_e = sqrt9.8 × 6.4 × 10⁶= sqrt6.272 × 10⁷. v_e approx 7.92 × 10³ m/s approx 7.9 km/s . 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.