The value of m given that the temperature of the mixture is 70°C is : 0.875 Kg
Applying the principle of energy conservation
Heat lost by the hot body = heat absorbed by the cold water + calorimeter
= m * 4200 * ( 100 - 70 ) = 0.50 * 4200 * ( 70 -20 ) + 105 * ( 70 -20 )
= m * 126000 = 110250
therefore ;
m = 110250 / 126000
= 0.875 kg
Hence we can conclude that The value of m given that the temperature of the mixture is 70°C is : 0.875 Kg
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