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प्रश्न
To study energy exchange between hot and cold objects, the system of both objects is isolated from the environment by keeping them inside ______.
विकल्प
a heat-resistant box
a rectangular box
Hope’s apparatus
None of these
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उत्तर
To study energy exchange between hot and cold objects, the system of both objects is isolated from the environment by keeping them inside a heat resistant box.
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संबंधित प्रश्न
What amount of heat must be supplied to 2.0 x 10-2 kg of nitrogen (at room temperature) to raise its temperature by 45 °C at constant pressure? (Molecular mass of N2 = 28; R = 8.3 J mol-1 K-1.)
Calculate the mass of ice required to lower the temperature of 300 g of water 40°C to water at 0°C.
(Specific latent heat of ice = 336 J/g, the Specific heat capacity of water = 4.2J/g°C)
What property of water makes it an effective coolant?
Give one example where high specific heat capacity of water is used as heat reservoir ?
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.
Why do bottled soft drinks get cooled, more quickly by the ice cubes than by the iced water, both at 0℃?
Indian style of cooling drinking water is to keep it in a pitcher having porous walls. Water comes to the outer surface very slowly and evaporates. Most of energy needed for evaporation is taken from the water itself and the water is cooled down. Assume that a pitcher contains 10 kg of water and 0.2 g of water comes out per second. Assuming no backward heat transfer from the atmosphere to the water, calculate the time in which the temperature decrease by 5°C. Specific heat capacity of water = 4200 J kg−1 °C−1 and latent heat of vaporization of water = 2.27 × 106 J kg−1.
Give one example where high specific heat capacity of water is used as cooling.
What change in heat energy occurs when lead at its melting point
solidifies without change in the temperature?
What are the factors on which the quantity of heat given to a body depends?
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.
Calculate the amount of heat released when 5.0 g of water at 20°C is changed into ice at 0°C.
(Specific heat capacity of water = 4.2 J/g°C
Specific latent heat of fusion of ice = 336 J/g)
The molar specific heat of a gas at constant volume is 12307.69 J kg-1 K-1. If the ratio of the two specific heats is 1.65, calculate the difference between the two molar specific heats of gas.
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")`
Numerical Problem.
How much heat energy is required to change 2 kg of ice at 0°C into water at 20°C? (Specific latent heat of fusion of water = 3,34,000 J/kg, Specific heat capacity of water = 4200 JKg–1K–1).
Match the following
| 1. | Specific heat capacity | a. | Dewar bottle |
| 2. | Calorimeter | b. | Lavoisier and Simon |
| 3. | Vacuum flask | c. | J Kg-1 K-1 |
| 4. | Ice – calorimeter | d. | Heat capacity |
A metal ball of heat capacity 50J/°C loses 2000 J of heat. By how much will its temperature fall?
Two blocks P and Q of different metals having their mass in the ratio 2 : 1 are given same amount of heat. Their temperature rises by same amount. Compare their specific heat capacities.
Calculate the amount of heat energy required to raise the temperature of 200 g of copper from 20°C to 70°C. Specific heat capacity of copper = 390 J kg-1 K-1.
