| Author | Message | ||
     971041 Username: 971041 Registered: 04-2003 |
>.<唔識計呀.........除了第一題外 點算好 | ||
| 971004 Username: 971004 Registered: 04-2003 |
ya, me too~ (actually, i haven't start to do it yet....) how to calcuate the question related with the angle of friction? | ||
| Lau Kai Kwong Username: lkk Registered: 04-2003 |
花姐，你想我答你乜好？舉個例子，你計第二題有甚麼困難呀？ LCM，你未計就話唔識計…你諗多陣先啦… | ||
| 971004 Username: 971004 Registered: 04-2003 |
我諗過第2題架啦.... let左條梯同地面個angle,跟住就無從入手啦. 睇返之前d note都唔係好得. | ||
| Lau Kai Kwong Username: lkk Registered: 04-2003 |
你有冇試過畫過force diagram？ | ||
| 971004 Username: 971004 Registered: 04-2003 |
ya, 1.is there exist a friction between the vertical wall and the stair?(i think there is) 2.after i draw the force diagram, is the force of the both contact of the stair to the wall are equal? 3.and, how to apply the angle of friction? | ||
| 971041 Username: 971041 Registered: 04-2003 |
我個問題就係根本唔知由邊度開始計 個force diagram又唔知畫得正唔正確>.< | ||
| Lau Kai Kwong Username: lkk Registered: 04-2003 |
To 花姐，首先就梗係畫force diagram 啦，當然force diagram 係有可能畫錯，但可以根據筆記的次序考慮，weight, reaction, friction, tension 等等… 睇下有冇漏forces，最後咪諗下d方向有冇錯囉。 跟住就係咁計落去… | ||
| Lau Kai Kwong Username: lkk Registered: 04-2003 |
To LCM, 1. 題目話係smooth定係rough丫？rough即係有friction啦。或者有冇提及它的coefficient of friction 丫？有的當然又即係話有friction啦… 2. 最初要假設所有力都不同，除非有對稱特性；然後再利用force resolution 來決定那一些力相等或不相等。 3. 在limiting equilibrium 的情況下，F=mR，或F=tanlR。 | ||
| 971041 Username: 971041 Registered: 04-2003 |
ai...我想問下~ [against a smooth plane inclined at 30 degree to the horizontal] 係個plane inclined at 30 degree 定係ladder inclined at 30 degree ?? | ||
| Lau Kai Kwong Username: lkk Registered: 04-2003 |
"plane inclined at 30 degree" |