问题描述：
大学里的物理题目 in english!
A stone is released from a balloon that is descending at a constant speed of 10 m/s. Neglecting
air resistance, after 20 s the speed of the stone is:
2160 m/s
1760 m/s
206 m/s
196 m/s
186 m/s
ans: C
为什么为什么!
A stone is released from a balloon that is descending at a constant speed of 10 m/s. Neglecting
air resistance, after 20 s the speed of the stone is:
2160 m/s
1760 m/s
206 m/s
196 m/s
186 m/s
ans: C
为什么为什么!
问题解答：
我来补答展开全文阅读