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Question
What is the Greenhouse effect?
Solution
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
RELATED QUESTIONS
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.
Liquid ammonia is used in ice factory for making ice from water. If water at 20°C is to be converted into 2 kg ice at 0°C, how many grams of ammonia are to be evaporated? (Given: The latent heat of vaporization of ammonia = 341 cal/g)
What do you mean by the statement?
'The specific latent heat capacity of fusion of ice is 336 J per g'?
What is the name given to the energy absorbed during a phase change?
Explain why water is used in hot water bottles for fomentation and also as a universal coolant.
Explain, why no tracks are left on the ice during ice skating?
State the main precautions to be taken in finding the latent heat of steam.
If there is no Heat loss to the surroundings, the heat released by the condensation of m1 g of steam at 100°C into water at 100°C can be used to convert m2 g of ice at 0°C into water at 0°C.
(i) Find:
(a) The heat lost by steam in terms of m1
(b) The heat gained by ice in terms of m2
(ii) Form a heat equation find the ratio of m2 : m1
Specific latent heat of vaporization of steam = 2268 kJ/kg
Specific latent heat of fusion of ice = 336 kJ/kg
Specific heat capacity of water = 4200 J/kg°C
If pressure increases, the melting point of a substance ______.
When ice is converted into water : constant temperature : : before the water evaporates : _______
Find the odd one out and give its explanation.
Match the columns.
| Column A | Column B |
| 1) Absolute humidity | a) J or cal |
| 2) Latent heat | b) J/kg °C |
| 3) Specific heat capacity | c) kJ/kg |
| 4) Heat | d) no unit |
| e) kg/m3 |
Write the name.
Products obtained when sugar is heated.
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Write scientific reason.
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Calculate the amount of heat required to convert 200g of ice at 0°C into the water at 0°C Specific latent heat of fusion of ice = 336 Jg-1
20 g of ice at 0°C absorbs 10,920 J of heat energy to melt and change to water at 50°C. Calculate the specific latent heat of fusion of ice. Specific heat capacity of water is 4200 J kg-1 K-1.
