Advertisements
Advertisements
प्रश्न
Water in lakes and ponds do not freeze at once in cold countries. Give a reason is support of your answer.
Advertisements
उत्तर
The specific latent heat of fusion of ice is sufficiently high (= 336 J g-1), and so to freeze water, a large quantity of heat has to be withdrawn. Hence, it freezes slowly and thus keeps the surroundings moderate.
संबंधित प्रश्न
A geyser heats water flowing at the rate of 3.0 litres per minute from 27 °C to 77 °C. If the geyser operates on a gas burner, what is the rate of consumption of the fuel if its heat of combustion is 4.0 × 104 J/g?
Name the S.I. unit of heat.
Write the expression for the heat energy Q received by the substance when m kg of substance of specific heat capacity c Jkg-1 k-1 is heated through Δt° C.
A mass m1 of a substance of specific heat capacity c1 at temperature t1 is mixed with a mass m2 of other substance of specific heat capacity c2 at a lower temperature t2. Deduce the expression for the temperature t of the mixture. State the assumption made, if any.
45 g of water at 50°C in a beaker is cooled when 50 g of copper at 18° C is added to it. The contents are stirred till a final constant temperature is reached. Calculate this final temperature. The specific heat capacity of copper is 0.39 J g-1K-1 and that of water is 4.2 J g-1K-1. State the assumption used.
Give three reasons for the increase of green house gases.
Define heat capacity.
Explain, why water is considered as best liquid for quenching thirst?
Why are athletes advised to put on extra clothes after competing on event?
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 Specific heat capacity of lead.
