[理工] [物理]-請問一些定律問題

[pugboy (緣投肥)]

不好意思 我想問各位物理高手兩題分別為
（a）on mars,the acceleration due to gravity is 3.71 m/s2. What could a rock's
velocity be 3s after you dropped it on mars？

how far would a rock fall in 3 s if you dropped it on mars?

問題（a）的解答我只想得出3.71 * 3 =11.13m
1/2*3.71*3^3＝51.08m
之後就不之如何求解...

（b）the builders of the pyramids used a long ramp to lift
20000-kg(22-ton)blocks.if a block rose 1 m in height while traveling 20 m
along the ramp's surface, how much uphill force was needed to push it up the
ramp at constant velocity

how much work was done in raising one of the blocks in problem 15 a height of
50 m

問題（b）我只想到m*g*sin系塔＝F
意思是20M*9.8*sin系塔 ＝答案嗎？
sin系塔又如何求出...？
b的第二問題是把20m改成50m就ok嗎？
麻煩一下 感恩！

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◆ From: 122.117.10.111
推 fairwarning:格式要加  -  喔
→ fairwarning:在[物理]面要加 -
→ fairwarning:物理的格式是[]                     ^^
※ 編輯: pugboy          來自: 122.117.21.138       (10/14 12:48)
推 youmehim:(a)H=0.5gt^2 (b) F=mgsinθ sinθ=1/20     W=mgh
→ pugboy:不好意思再問一下 （a）小題中的第二個問題是求how far 可
→ pugboy:是H＝0.5*g*t^2 那how far 是 m*t嗎 那m是如何求？
→ pugboy:還有(b)小題中W＝mgh 裡得h＝0.5*g*t^2 中的t如何求出？
→ pugboy:感恩..！
推 youmehim:(a) 哪來的m.. (b) h = 50m
→ pugboy:我是想請問（a）小題的第二小題不是求how far嗎 可是H不是
→ pugboy:高度嗎？這樣要如何求出how far？
→ pugboy:還有（b）小題的第二小題H=50M 那w=mgh中的m要如何求出..
→ pugboy:不好意思 小弟是物理白痴 不懂太多 麻煩可以幫我解惑 感恩