ICSE Class 10 Physics 2018 Solved Paper

© examsnet.com
Question : 68
Total: 78
The temperature of 170g of water at 50C is lowered to 5C by adding certain amount of ice to it. Find the mass of ice added.
Given : Specific heat capacity of water =4200
Jkg1C1 and Specific latent heat of ice =336000Jkg1.
Solution:  
Given : mass of the water =170g=
170
1000
kg
,
Initial temperature =50C .
Let the mass of ice added be = ' x ' kg
Given that the final temperature of mixture =5C
Heat lost by water =m×c×T
=
170
1000
×4200
×(505)

=32130J
Now the change in ice will be as
Ice at 0C Water at 0C Water at 5C
Heat gained by ice
=mL+mcT
=x×336000+x×4200×(50)
=336000x+21000x
=357000xJ
By the principle of calorimetry,
Heat lost by water = Heat gained by ice
32130=357000x
or x=
32130
357000

=0.09kg or 90g
© examsnet.com
Go to Question: