本题目来源于试卷: Overweight and underweight,类别为 美国物理杯赛(Physics Bowl)
[单选题]
00.12: Astronauts in an orbiting space shuttle arw s;5xg76kf:3 htyjyz e “weightlesj7.r46td/uhcx n:j5).x hoh(d a;fwqz-fem ys” because
A. of their extreme distance from the earth
B. the net gravitational force on them is zero
C. there is no atmosphere in space
D. the space shuttle does not rotate
E. they are in a state of free fall
参考答案: E
本题详细解析:
暂无
|