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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
A solid of mass 50 g at 150 °C is placed in 100 g of water at 11 °C when the final temperature recorded is 20 °C. Find the specific heat capacity of the solid. (specific heat capacity of water = 4.2 J/g °C)
Calculate the mass of ice needed to cool 150 g of water contained in a calorimeter of mass 50 g at 32 °C such that the final temperature is 5 °C. Specific heat capacity of calorimeter = 0.4 J g-1 °C-1, Specific heat capacity of water = 4.2 J g-1°C-1, latent heat capacity of ice = 330 J g-1.
What do you understand by the following statements:
The specific heat capacity of lead is 130 Jkg-1K-1.
Write the approximate value of specific heat capacity of water in S.I. unit.
What do you mean by the following statement?
The specific heat capacity of copper is 0. 4 Jg-1 K-1?
Why do the farmers fill their fields with water on a cold winter night?
Water is used in hot water bottles for fomentation. Give a reason.
In an experiment to determine the specific heat capacity of a solid following operations were
made:
Mass of calorimeter + stirrer = x kg
Mass of water = y kg
Initial temperature of water t1℃
Mass of solid = z kg
Temperature of solid = t2 ℃
Temperature of mixture = t ℃
Specific heat capacity of calorimeter and water are c1 and c2 respectively. Express the specific
heat capacity c of the solid in terms of the above data.
How does green house effect help in keeping the temperature of earth’s surface suitable for living of human beings?
Specific heat capacity of substance A is 3.8 J g-1 K-1whereas the specific heat capacity of substance B is 0.4 J g-1 K-1. Which of the two is a good conductor of heat? How is one led to this conclusion?
If, in a central heating system, steam enters a radiation pipe at 100°C and water leaves the radiation pipe at 100°C, can this radiation pipe heat a room? Give an explanation for your answer.
From the options given below the specific heat of _______ is maximum.
Read this activity and answer the following questions.
- Take three spheres of iron, copper and lead. the lead of equal mass.
- Put all the three spheres in boiling water in the beaker for some time.
- Take the three spheres out of the water.
- All the spheres will be at a temperature 100 °C.
- Put them immediately on the thick slab of wax.
- Note, the depth that each of the sphere goes into the wax.
Questions:
- Which property is determined from this activity?
- Give name to that property.
- Explain the term principal of heat exchange with the help of this activity.
Explain why the specific heat capacity at constant pressure is greater than the specific heat capacity at constant volume.
Two metals A and B have specific heat capacities in the ratio 2:3. If they are supplied same amount of heat then
If the mass ratio of metal A and metal B is 3:5 then calculate the ratio in which their temperatures rise.
Two metals A and B have specific heat capacities in the ratio 2:3. If they are supplied same amount of heat then
If specific heat capacity of metal A is 0.26 Jg-1 0C-1 then calculate the specific heat capacity of metal B.
The specific heat capacity of ______ is maximum.
A geyser heats water flowing at a rate of 2.0 kg per minute from 30°C to 70°C. If the geyser operates on a gas burner, the rate of combustion of fuel will be ______ g min-1.
[Heat of combustion = 8 × 103 Jg-1 Specific heat of water = 4.2 Jg-1°C-1]
