F.3 Physics問題 !!! [復制鏈接]

A metal block of 0.250 kg is heated by a 500度 bunsen flame before it's immersed into 2kg of water at 25度 . What is the final temperature of the metal-water system ?
Give that the specific heat capacity of the metal is 350 J
Give that the specific heat capacity of the water is 4200 J

點計???

Let T be the required final temperature

Energy loss from the metal block= energy gained by the water
    (do it yourself)

Hint :use E=mcΔT for this question



PS:

"Give that the specific heat capacity of the metal is 350 J
Give that the specific heat capacity of the water is 4200 J"

wrong unit!!

D metal比五百度既火燒唔一定會變五百度架wor

引用第2樓abbrian2005於2007-06-07 20:29發表的“”:
D metal比五百度既火燒唔一定會變五百度架wor [表情]

ARAR ...
yea...

睇錯左...

sorry

．．．．．．       ＝____＝ """""""


唔當佢去到５００度既話......
根據現有資料真係唔知點計.....

唯有等ｄ勁人出馬...

有無講舊metal 一開始幾多度?

引用第5樓智者於2007-06-07 20:54發表的“”:
有無講舊metal 一開始幾多度? [表情]
0.25 x 350 x (500-25) = 2 x 4200 x T
自己計 [表情]

冇講,連heat幾耐都唔講

0.25 x 350 x (500 - T) = 2 x 4200 x (T - 20)

assume no energy loss to surrounding
assume the metal block is heated up to 500℃ before it's immersed into water

0.25 x 350 x (500 - T) = 2 x 4200 x (T - 25)
assume no energy loss to surrounding
assume the metal block is heated up to 500℃ before it's immersed into water

呢個應該arm

錯的

o個舊metal 係咪copper 呀...
我都唔記得....
應該知佢個溶點.....
if 佢未溶o既話可能真係會上到500 計架喎.....

AND 我應為係最後個METAL 同 個WATER 會係EQUAL in temperature....
所以...
有o的唔同意智者o個個....

引用第7樓萊斯特於2007-06-07 21:05發表的“”:
0.25 x 350 x (500 - T) = 2 x 4200 x (T - 20)
assume no energy loss to surrounding
assume the metal block is heated up to 500℃ before it's immersed into water

應該係final 減 initial.....

其實我計到係20....
好似唔合理....

引用第10樓someone於2007-06-07 21:13發表的“”:
o個舊metal 係咪copper 呀...
我都唔記得....
應該知佢個溶點.....
if 佢未溶o既話可能真係會上到500 計架喎.....
.......

唔係去唔去倒既問題
問題係題目冇講有冇去到

haha

d heat既野比番哂呀sir