The escape velocity of the surface of earth is given by, ve=√2gRe Substitute 6400km for Re and 10m∕s2 for g in equation (I). ve‌‌=√2(10m∕s2)(6400km×‌
103m
1km
) ‌‌=11.3×103m∕s ‌‌=11.3km∕s ‌‌≈12km∕s When g′=2g And R′=‌