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प्रश्न
State factors on which the amount of heat radiated by a body depends.
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उत्तर
The amount of heat radiated by a body depends on:
- The absolute temperature of the body (T)
- The nature of the body – the material, nature of the surface - polished or not, etc.
- The surface area of the body (A)
- Time duration for which body emits radiation (t).
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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?
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.
Differentiate between heat capacity and specific heat capacity.
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.
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 ?
Ice cream appears colder to the mouth than water at 0℃. Give reason.
State the effect of enhancement of green house effect.
How will climate changes affect the various animal species?
Who shall pay carbon tax ?
The global warming has resulted:
(a) the increase in yield of crops
(b) the decrease in sea levels
(c) the decrease in human deaths
(d) the increase in sea levels
What is meant by specific heat capacity?
The substances like water which have ........... Heat capacity warm up more slowly than substances like iron which have .......... heat capacity.
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A liquid X has specific heat capacity higher than the liquid Y. Which liquid is useful as coolant in car radiators.
A piece of iron of mass 2.0 kg has a heat capacity of 966 J K-1. Find its specific heat capacity in S.I unit.
m kg of a substance of specific heat capacity s J/kg °C is heated so that its temperature rises from θ1°C to θ2°C. Write down the expression for the heat Q supplied.
A certain amount of heat Q will warm 1 g of material X by 3°C and 1 g of material Y by 4°C. Which material has a higher specific heat capacity?
1 kg of water freezes to form ice at 0°C. What amount of heat is withdrawn?
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Solve the following problem.
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The cold object the hot object enclosed in one box of heat-resistant material.
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Consider the statement given below and choose the correct option.
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Reason: The thermal energy is transferred from one part of a substance to another part without the actual movement of the atoms or molecules.
Explain why the specific heat capacity at constant pressure is greater than the specific heat capacity at constant volume.
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Thermal capacities of substances A and B are same. If mass of A is more than mass of B then:
Which substance will have more specific heat capacity?
