Advertisements
Advertisements
प्रश्न
1 kg of molten lead at its melting point of 327°C is dropped into 1 kg of water at 20°C. Assuming no loss of heat, calculate the final temp. of water. (Sp. heat of lead = 130 J/kg°C, latent heat of lead = 27000 J/kg and Sp. heat of water = 4200 J/kg°C).
उत्तर
Let the final temperature of the mixture be t
Heat lost by lead = Heat gained by water
m1L + m1 x CL x (327 - t) = mz x cw x (t - 20)
1 x 27000 + 1 x 130 x (327 - t) = 1 x 4200 x (t - 20)
27000 + 42510 _ 130t = 4200t - 84000
t = 35.45°C
So, the final temperature of water is 35.45°C.
APPEARS IN
संबंधित प्रश्न
200 g of hot water at 80°C is added to 400 g of cold water at 10°C. Neglecting the heat taken by the container, calculate the final temperature of the mixture of water. Specific heat capacity of water = 4200 J kg-1K-1.
Explain the terms melting ?
Express -400C on the Fahrenheit scale.
What mass of ice at 0°C will be required to cool 0.9 kg of water from 35°C to 0°C? Assume all the ice used melts. The specific heat capacity of water is 4.2 x 103 J/kgoC and specific latent heat of fusion of ice is 336 x 103 J/kg.
Name two factors on which the heat energy librated by a body on cooling depends.
Why do doctors advise to put a strip of wet cloth on the forehead of a person having high fever (temperature)?
40g of ice at 0°C is used to bring down the temperature of a certain mass of water at 60°C to 10°C. Find the mass of water used.
[Specific heat capacity of water = 4200 J kg-1 °C-1]
[Specific latent heat of fusion of ice = 336 × 103 J kg-1]
250 g of water at 30 °C is present in a copper vessel of mass 50 g. Calculate the mass of ice required to bring down the temperature of the vessel and its contents to 5 °C.
Specific latent heat of fusion of ice = 336 × 103 J kg-1
Specific heat capacity of copper vessel = 400 J kg-1 °C-1
Specific heat capacity of water = 4200 J kg-1 °C-1.
The device which is used to measure the heat capacity of the liquid is ______.