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???
萊斯特
2007-06-07 18:10
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!!
Mr-Brian
2007-06-07 20:29
D metal比五百度既火燒唔一定會變五百度架wor
萊斯特
2007-06-07 20:34
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
萊斯特
2007-06-07 20:52
．．．．．． ＝____＝ """""""
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...
智者
2007-06-07 20:54
有無講舊metal 一開始幾多度?
Mr-Brian
2007-06-07 21:04
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
萊斯特
2007-06-07 21:05
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
智者
2007-06-07 21:08
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
智者
2007-06-07 21:10
錯的
someone
2007-06-07 21:13
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....
someone
2007-06-07 21:14
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
我所講既WATER TO STREAM意思即係舊metal係放左落水個一刻, the water around the metal is heated up to 100 degree(the heat may not be distributed throughout the whole system, as heat need time to be transferred) and gain latent heat and become stream
PS:and also leave the system and the energy gained by these mass of water will never return this can be treated as "energy loss to surrounding" so that's why i said "唔知洗唔洗假設埋"
someone
2007-06-07 23:40
我同alvin o既計法一樣....
我覺得中三唔駛諗咁多.....
Bun
2007-06-07 23:51
引用第31樓萊斯特於2007-06-07 23:36發表的“”: 我所講既WATER TO STREAM意思即係舊metal係放左落水個一刻, the water around the metal is heated up to 100 degree(the heat may not be distributed throughout the whole system, as heat need time to be transferred) and gain latent heat and become stream .......
...
i know~
