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प्रश्न
What is the Greenhouse effect?
उत्तर
The green house effect is the phenomenon in which infrared radiations of long wavelength given out from the surface of a planet are absorbed by its atmospheric gases to keep the environment at the planet's surface and the lower atmosphere warm.
The green house gases present in the earth's atmosphere play a role similar to that of glass walls of a green house. Hence this phenomenon is called the green house effect.
The increase in the concentration of carbon dioxide due to above human activities is responsible for 60% increase in green house effect
संबंधित प्रश्न
Write the approximate value of specific latent heat of ice.
Explain the following:
The heat supplied to a substance during it change of state, does not cause any rise in its temperature.
Calculate the total amount of heat energy required to convert 100 g of ice at −10℃ completely into water at 100℃. Specific heat capacity of ice = 2.1 J g-1 K-1, specific heat capacity of water = 4.2 J g-1K-1, specific latent heat of ice = 336 J g-1.
Answer the following:
Explain the role of latent heat in the change of state of a substance.
Define the following terms:
(i) Specific latent heat,
(ii) Specific latent heat of fusion.
What is the name given to the energy absorbed during a phase change?
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.
Define the term ‘specific latent heat of fusion’ of a substance.
Why does evaporation causes cooling and why is water used in hot water bottles?
What do you understand by the ‘latent heat of vaporization’ of a substance?
State two advantages of the high specific latent heat capacity of steam, which is about 226 × 104 J/kg?
Calculate the total amount of heat required to convert 100g ice at 0°C to steam at 100°C.
(Specific latent heat of fusion of ice = 336 J/g, specific latent heat of vaporization of steam = 2260 J/g, specific heat capacity of water = 4.2 J/g°C).
1 kg of water is contained in a 1.25 kW kettle. Assuming specific heat capacity of water = 4.2 J/g °C and specific latent heat of vaporization = 2260 J/g, calculate:
(i) the time taken for the temperature of water to rise from 25°C to its boiling point,
(ii) the mass of water which evaporates per minute from the boiling water.
During reheating, ice is converted to water at a temperature of 0 °C.
1 kg of dry air at a temperature of 40 °C can hold a maximum of 49 g of water vapour.
Write scientific reason.
The bottom of some steel utensils used for cooking is copper.
Define specific latent heat capacity
