# Milk in your Tea.If 0.2 l (litre, = 1000 cm3 = 0.001 m3) of tea at 85degrees is added to 0.03 l of milk at 5de?

If 0.2 l (litre, = 1000 cm3 = 0.001 m3) of tea at 85degrees is added to 0.03 l of milk at 5degrees, what is the final temperature of the mixture ? For simplicity, assume that the specific heat capacity, and density, of tea and milk are ~ the same.

Relevance

1 litre = 1000 ml = 1000cm^3 = 1/10^6 m^3

Tx = (0.2*85+0.03*5)/(0.2+0.03) = 74.6 °C

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• Let the final temperature is t*C

=>heat loss by tea = heat gained by milk

=>[ms∆t]for tea = [ms∆t]for milk

=>0.2 x 4187 x (85-t) = 0.03 x 4187 x (t-5)

=>71179 - 837.40t = 125.61t - 628.05

=>t = 74.57*C