The mass of one boulder is 1,000 kilograms, and the mass of the other boulder is 50 kilograms. If both of the boulders are moving at the same speed, which of the following statements is true when both reach point A before touching the ground? A. The 1,000-kg boulder has more kinetic energy than the 50-kg boulder. B. The 50-kg boulder has more kinetic energy than the 1,000-kg boulder. C. The boulders have the same kinetic energy. D. Neither boulder has any kinetic energy

Your starship, the aimless wanderer, lands on the mysterious planet mongo. as chief scientist-engineer, you make the following measurements: a 2.50-kg stone thrown upward from the ground at 14.0 m/s returns to the ground in 5.70 s ; the circumference of mongo at the equator is 2.20×10^5 km ; and there is no appreciable atmosphere on mongo. (a) the starship commander, captain confusion, asks for the following information: what is the mass of mongo? (b) if the aimless wanderer goes into a circular orbit 2.20×10^4 km above the surface of mongo, how many hours will it take the ship to complete one orbit? (c) an unmanned spacecraft is in a circular orbit around the moon, observing the lunar surface from an altitude of 44.0 km . to the dismay of scientists on earth, an electrical fault causes an on-board thruster to fire, decreasing the speed of the spacecraft by 23.0 m/s . if nothing is done to correct its orbit, with what speed (in km/h) will the spacecraft crash into the lunar surface?