A boy throws a stone vertically upwards with a speed 10ms^ -1 . Find the acceleration of the stone one second after leaving the boy's hand .
A. 0 ms^ -2
B. 5 ms^ -2 downwards
C. 10 ms^ -2 downwards
D. 5 ms^ -2 upwards
2007-03-10 07:45:55 · 2 個解答 · 發問者 William 3 in 科學 ➔ 其他：科學
Assume there is no air resistance.
Since there is no air resistance, so the only force acting on the stone is the weight of the stone.
Obviously, the acceleration of the stone at any time in the air is the acceleration due to gravity, 10 ms^-2 downward.
So the answer is C.
2007-03-10 11:29:21 · answer #1 · answered by Audrey Hepburn 7 · 0⤊ 0⤋
Apparently, the acceleration is from gavity, i.e. 10 m/s2 downward
2007-03-10 08:11:19 · answer #2 · answered by 天同 7 · 0⤊ 0⤋