" A particle is thrown vertically upwards. When the particle is at the max. height, its acceleration is ........"
A. pointing downwards
B. changing from upwards to downwards
C. changing from downwards to upwards
D. pointing upwards
(plz answer with explanation~ thz:)
f.4 physics
2009-01-01 10:55 pm
回答 (2)
2009-01-01 11:06 pm
✔ 最佳答案
A. pointing downwardsdue to gravity[[明?!
因為個particle雖然被thrown向上
但係其實一直被gravity向下拉住=)
參考: 我也是f.4生=) 之前測驗出過呢題[一模一樣*v*]
2009-01-02 1:35 am
Whenever there is a force, there is an acceleration.
The only force acting on the particle is its own weight, which is the downward pointing force of gravity. Thus, the acceleration is always pointing downward during the entire journey of the particle, including the instance when it is at the highest point.
The answer is option A.
The only force acting on the particle is its own weight, which is the downward pointing force of gravity. Thus, the acceleration is always pointing downward during the entire journey of the particle, including the instance when it is at the highest point.
The answer is option A.
收錄日期: 2021-04-29 17:26:45
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