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प्रश्न
Explain, Why is it advisabile to pour cold water over burns, caused on human body, by hot solids?
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उत्तर
Water has the highest specific heat capacity of 4.2 Jg-1°C-1. Thus, it can extract large amount of heat energy rapidly from the site of burn and hence gives a lot of relief.
संबंधित प्रश्न
A refrigerator converts 100 g of water at 20°C to ice at -10°C in 35 minutes. Calculate the average rate of heat extraction in terms of watts.
Given: Specific heat capacity of ice = 2.1 J g-1°C-1
Specific heat capacity of water = 4.2 J g-1°C-1
Specific latent heat of fusion of ice = 336 J g-1
Specific heat capacity of substance A is 3.8 J g-1K-1 whereas the specific heat capacity of substance B is 0.4 J g-1 K-1
(i) Which of the two is a good conductor of heat?
(ii) How is one led to the above conclusion?
(iii) If substances A and B are liquids then which one would be more useful in car radiators?
State, with reason, which of the two, boiling water or steam both at 100°C will produce more severe burns.
Explain, why is water sprayed on roads in evening in hot summer?
Write an expression for the heat energy liberated by a hot body.
The temperature of a lead piece of mass 400 g rises from 20°C to 50°C when 1560 J of heat is supplied to it. Calculate: Heat capacity of lead piece.
An electric immersion heater is rated 1250 W. Calculate the time in which it will heat 20 kg of water at 5°C to 65°C.
Numerical Problem.
What is the heat in joules required to raise the temperature of 25 grams of water from 0°C to 100°C? What is the heat in Calories? (Specific heat of water = `(4.18"J")/("g"°"C")`
Express the change in internal energy in terms of molar specific heat capacity.
