作者flygey (努力達成目標)
看板TransPhys
標題[考古] 請問兩題計算題
時間Fri Jul 11 15:48:58 2008
1.100度C,200g金屬塊,投入30度C,120g水中,混合後溫度40度C,假設無其他熱量進出,則此
金屬塊比熱為多少cal/g.k
請問一下 列式 200xSx(100-40)=120x1x(30-40) 這樣對嗎
可試算出來 S 是負數
2.An electron is launched with velocity v in a uniform magnetic field B.
The angle between v and B is between 0度 and 90度.As a result, the electron
follows a helix,its velocity vector v returming to its initial value in a
time interval of:
2pmvsinQ/eB 2pmv/eB 2pm/eB 2pmvcosQ/eB
請教以上兩題
感謝
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1F：→ xji4dk4bp6:應該是200xSx(100-40)=-[120x1x(30-40)] 才對 07/11 16:58