close
標題:

physics--heat

發問:

0.5 kg of ice at 0℃ is mixed with 1kg of water at 20℃. Assume that there is no heat transfer between the mixture and the surroundings. Find the final temperature of the mixture. ( specific heat capacity of water = 4200 J/kg/℃ specific latent heat of fusion of ice = 3.34 x 10^5 J/kg)

最佳解答:

aa.jpg

 

此文章來自奇摩知識+如有不便請留言告知

Assume that there is no heat transfer between the mixture and the surroundings: 0℃ is taken to be the reference temperature in this case: Heat required to melt 0.5 kg of ice = (0.5 kg)(3.34 x 10^5 J/kg) = 167000J Heat supplied from 1kg of water at 20℃ = (1 kg)(20℃)(4200 J/kg/℃) = 84000J Since heat supplied from 1kg of water at 20℃ is not sufficient to melt 0.5 kg of ice completely, there will be no increase in temperature from melting point, and the final temperature of the mixture is 0℃.

其他解答:

(m)(s)(T) = heat m=mass , s=specific heat of water , T = change of temp. first, ice increse temp while water decrese temp. because heat transfer from water to ice. (0.5)(s)(T-0) 3.34x10^5=(1)(s) (20-T) 左邊T-0 mean that ice fusion左之後變水再上升既temp. 而哩個change of temp. = water decrese左既溫度 =]
arrow
arrow

    ppi93gk88d 發表在 痞客邦 留言(0) 人氣()