An astronaut weighs 550 N on Earth. He lands on another planet which has a radius of 1/2 times greater than the Earth and finds that he still weighs 550 N. Show how this is possible using calculations.

During the apollo moon missions, astronauts were concerned about the effects of newton's third law of motion when: o a. they ejected waste water, because they were concerned that it would push them off course. o b. they reentered earth's atmosphere, because they were carrying heavy moon rocks. o c. they took off from earth, because a large force was required to generate large acceleration. o d. they detected incoming space debris, because the inertia of the debris could damage their ship.