Question: The condition of apparent weightlessness can be created momentarily when a plane flies over the top of a vertical circle. At a speed of 900 kmh−1 , the radius of the vertical circle that the pilot must use is
(A) 10.6 km
(B) 8.5 kg
(C) 6.4 km
(D) 4.0 km
Answer: option (C)
Solution:
