phy .. heat

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2007-01-08 4:38 am

Simon is preparing a cup of ice tea at 0 C. He needs to put ice cubes at 0 C into 250 ml hot tea at 50 C. How many ice cubes should Simon put into the tea?

Given:
mass of 1 ml of tea = 1g
mass of an ice cube = 40 g
specific latent heat of fusion of ice = 3.34 x 10^5 J kg^-1
specific heat capacity of water = 4200 J kg^-1 C^-1
specific heat capacity of tea = 4200 J kg^-1 C^-1

回答 (1)

用戶82648

2007-01-08 4:50 am

✔ 最佳答案

Let n be the number of ice cube
(0.001 x 250)(4200)(50 - 0) = (0.04n)(3.34 x 10^5)
n = 3.93
Simon should put 4 ice cube ito the tea

2007-01-10 03:09:08 補充：
如自再加埋個mc△T係energy gained 度咁個final溫度咪唔係0度囉又或者我咁計俾你睇energy lose = energy gain　　　　　　　　　mc△T = ml + mc△T(0.001 x 250)(4200)(50 - 0) = (0.04n)(3.34 x 10^5) + (0.04n)(4200)(0 - 0)　　　　　　　　　　　　　　　　　　　　　　　這個mc△T都係冇左　　　　　　　　　　　n = 3.93答案都係一樣

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