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प्रश्न
Explain the following temperature vs time graph.
उत्तर
- During the heating of ice, the change in temperature with time is shown in the graph.
- Seg AB - Seg AB represents the conversion of ice into the water at a constant temperature. During the melting of ice at 0°C, ice absorbs heat energy and this continues till all the ice converts into water.
- Seg BC - Once all ice is transformed into water, the temperature of water starts rising it increases up to 100°C. Seg BC represents a rise in the temperature of water from 0°C to 100°C.
- Seg CD - Even though the heat energy is supplied to the water after 100°C its temperature does not rise. The heat energy absorbed by water is used to break the bonds between molecules of the liquid to convert it into a gaseous state.
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संबंधित प्रश्न
State two factors upon which the rate of emission of thermions depends.
Write the approximate value of specific latent heat of ice.
A refrigerator converts 100g of water at 20℃ to ice at – 10℃ in 73.5 min. Calculate the average rate of heat extraction in watt. The specific heat capacity of water is 4.2 J kg-1 K-1, specific latent heat of ice is 336 J g-1 and the specific heat capacity of ice is 2.1 J kg-1 K-1.
Explain the following temperature vs time graph.
What is meant by latent heat? How will the state of matter transform if latent heat is given off?
A thermally insulated pot has 150 g ice at temperature 0°C. How much steam of 100°C has to be mixed to it, so that water of temperature 50°C will be obtained? (Given : latent heat of melting of ice = 80 cal/g, latent heat of vaporization of water = 540 cal/g, specific heat of water = 1 cal/g °C)
Water expands on reducing its temperature below ______°C.
A substance changes from its solid state to the liquid state when heat is supplied to it. What name is given to heat absorbed by the substance.
Name two factors on which the heat absorbed or given out by a body depends.
Explain why water is used in hot water bottles for fomentation and also as a universal coolant.
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The latent heat of vaporisation is a term referred for the conversion of gas into liquid.
Write scientific reason.
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Write scientific reason.
Use a pressure cooker to cook food in cold air.
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The diagram below shows a cooling curve for a substance:
- State the temperatures at which the substance condenses.
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- Why do we prefer ice to ice-cold water for cooling a drink?
