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प्रश्न
Read the passage and answer the questions based on it.
If heat is exchanged between a hot and cold object, the temperature of the cold object goes on increasing due to gain of energy and the temperature of the hot object goes on decreasing due to loss of energy. The change in temperature continues till the temperatures of both objects attain the same value. In this process, the cold object gains heat energy and the hot object loses heat energy. If the system of both the objects is isolated from the environment by keeping it inside a heat-resistant box then no energy can flow from inside the box or come into the box. In this situation, we get the following principle.
Heat energy lost by the hot object = Heat energy gained by the cold object. This is called the ‘Principle of heat exchange’.
- Where does heat transfer take place?
- In such a situation which principle of heat do you perceive?
- How can this principle be explained in short?
- Which property of the substance is measured using this principle?
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उत्तर
- Heat is transferred from hot object to cold object.
- During the transfer of heat from hot object to cold object we perceive the principle of heat exchange.
- As inside the heat resistant box, the heat lost by hot object exactly equals heat gained by cold object, principle of heat exchange is stated as:
In an isolated system,
Heat energy lost by hot object = Heat energy gained by cold object. - Specific heat of the substance is measured using the principle of heat exchange.
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संबंधित प्रश्न
Name the S.I. unit of heat.
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.
Explain the term boiling ?
How does green house effect help in keeping the temperature of earth’s surface suitable for living of human beings?
Give three reasons for the increase of green house gases.
650 J of heat is required to raise the temp. of 0.25 kg of lead from 15°C to 35°C. Calculate the Sp. heat capacity of lead.
Water boils at 120 °C in a pressure cooker. Explain the reason.
What are the factors on which the quantity of heat given to a body depends?
Write two advantages of high specific heat capacity of water.
If substances A and B are liquids then which one would be more useful in car radiators?
Given: Specific heat capacity’A’ 3.8 J/g /K. Specific heat capacity ‘B’ 0.4 J/g /K.
Will the value of specific heat’capacity and specific latent heat of a substance change if the scale is °F instead of °C?
A piece of ice is heated at a constant rate. The variation of temperature with heat input is shown in the graph below:
(i) What are represented by AB and CD?
(ii) What conclusion can you draw regarding the 110°c nature of ice from the above graph?
A piece of iron of mass 2.0 kg has a thermal capacity of 966 J/°C. What is its specific heat capacity in S.I. units?
Calculate the ratio of two specific heats of polyatomic gas molecules.
How much heat energy is necessary to raise the temperature of 5 kg of water from 20°C to 100°C?
Derive Meyer’s relation for an ideal gas.
For a gas `"R"/"C"_"v" = 0.4,` where 'R' is the universal gas constant and 'Cv' is molar specific heat at constant volume. The gas is made up of molecules which are ______.
The ratio of the specific heats `c_"p"/c_"v"=gamma` in terms of degrees of freedom 'n' is given by ______.
A block of ice of mass 120 g at temperature 0°C is put in 300 gm of water at 25°C. The xg of ice melts as the temperature of the water reaches 0°C. The value of x is ______.
[Use: Specific heat capacity of water = 4200 Jkg-1K-1, Latent heat of ice = 3.5 × 105 Jkg-1]
When two kilocalories of heat are supplied to a system, the internal energy of the system increases by 5030 J and the work done by the gas against the external pressure is 3350 J. Calculate J, the mechanical equivalent of heat.
