[DSE Physics] Newton's second law of motion 牛頓運動第二定律

#DSE #Physics
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[@chenchuanshui6858]

How about the rolling friction or sliding friction?
Any moving object still have friction right just smaller than static friction
Right?

[@MarcYam]

Yep you are right.
And all the concepts you mentioned are out of syllabus.😅😅😅

[@AndyLWT]

F=ma if the motion is move in constant velocity . Then , a is it =0ms-2?

[@256dan5]

Yes sure

[@8octopus763]

恩師！請受小妹一拜🙇🏻‍♀️😂😂

[@user-fs6yd1yx6p]

net force作用係架車係0，咁架車係點樣move in uniform velocity?
假設act 1N force 落車到一秒，咁架車就會以 (1/m)ms-1的速率運行？

[@MarcYam]

呢個世界就係咁奇怪，無net force架車都可以move in uniform velocity，少許違反直覺，所以伽里略同牛頓咁偉大就係咁解。

[@kdkdkidi5605]

for5:19 如果answer is 10N k就=10？

[@MarcYam]

對，但我地而家已經定咗k係1，唔會無啦啦寫k係10呀喇！

[@kdkdkidi5605]

即啲科學家已經將k定性為1？ k is including in Unit:(newton?)

[@MarcYam]

YES

[@dirtymud54987]

與空氣產生摩擦呢？

[@longname6117]

即係 air resistance 空氣阻力

[@user-mj5tj7ju2x]

有淨力就有速度既改變而並非速度,咁有啲咩物件從一開始就有以恆速運動?😳😅

[@MarcYam]

咁就要問乜嘢叫一開始喇😅

[@ptd2724]

咩係unbalanced force?

[@MarcYam]

czcams.com/video/1okidHFQ66U/video.html
睇睇條片幫唔幫你？

[@ptd2724]

@@MarcYam oh,resultant force =unbalanced force