Heat

ting

Which of the following can increase the sensitivity of liquid-in-glass  thermometer?

1)Use a narrower capillary tube
2) use a liquid of lower S.H.C
3)Use a bulb with thinner glass walls

i am wondering whether (2) is correct or not~.~

[ 本帖最後由 ting 於 23/9/2007 03:20 PM 編輯 ]

雪貓

2應該是吧...
SHC低就代表只要少少heat 就可升1度....
1也是對,3就不對~.~

sapphire

i think 1,2 just can increase the accuracy of the thermometer
only 3 can increase the sensitivity

i am not good in physics and hv forget everything about heat. just a guess, sorry orz

雪貓

原帖由 sapphire 於 21/9/2007 10:15 PM 發表

                               
登錄/註冊後可看大圖

i think 1,2 just can increase the accuracy of the thermometer
only 3 can increase the sensitivity

i am not good in physics and hv forget everything about heat. just a guess, sorry orz

3不是只是decreasethe time for the thermometer to respond嗎?

修改了- -

[ 本帖最後由 雪貓 於 21/9/2007 10:41 PM 編輯 ]

sapphire

原帖由 雪貓 於 21/9/2007 10:28 PM 發表

                               
登錄/註冊後可看大圖

3不是只是increase the time for the thermometer to respond嗎?

其實我也不知道sensitivity的定義是什麼

thinner glass wall能減低time respond,但這是不是代表加強對temperature的感應就不知道了
===========================================================================
問了某個physics很強的fd
1,2 也能加強sensitivity和accuracy
3那個......他說某程度上算,總覺得問得蠻模糊的

雪貓

原帖由 sapphire 於 21/9/2007 10:36 PM 發表

                               
登錄/註冊後可看大圖

其實我也不知道sensitivity的定義是什麼

thinner glass wall能減低time respond,但這是不是代表加強對temperature的感應就不知道了
======================================================================= ...

打錯了increase- -""
我記得好像說thinner wall只是令heat快點傳遞到中間的liquid
sensitivity不是即是少少轉變都能感應到嗎@@""

[ 本帖最後由 雪貓 於 21/9/2007 10:41 PM 編輯 ]

sapphire

原帖由 雪貓 於 21/9/2007 10:40 PM 發表

                               
登錄/註冊後可看大圖

sensitivity不是即是少少轉變都能感應到嗎@@""

真的忘了 orz

看到sensitivity時我第一個就想到和time respond有關,之後才想到和respond for small changes有關......

ting

其實
原本問題是這樣的
1)Use a WIDER capillary tube
2) use a liquid of lower S.H.C
3)Use a bulb with thinner glass walls

A) (1)only
B) (3)only
C) (1)(2)
D)(2)(3)

1必錯
所以只剩下B和D
因此3是對的?

只是想知道更多
把問題改了ORZ

[ 本帖最後由 ting 於 21/9/2007 11:13 PM 編輯 ]

sapphire

this time ask another physics expert orz
==============================================================
the less the time for reaching the correct reading, the higher is the sensitivity

2. specific heat capacity ↓  -->  energy for increasing 1 C ↓ --> temperature increase faster --> volume increase faster --> time for reaching the correct reading ↓

3. thinner glass wall --> time for transferring heat energy to the liquid ↓ --> volume increase faster --> time for reaching the correct reading ↓