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प्रश्न
Why do the farmers fill their fields with water on a cold winter night?
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उत्तर
In the absence of water, if on a cold winter night the atmospheric temperature falls below 0oC,
the water in the fine capillaries of plant will freeze, so the veins will burst due to the increase in
the volume of water on freezing. As a result, plants will die and the crop will be destroyed. In
order to save the crop on such cold nights, farmers fill their fields with water because water has
high specific heat capacity, so it does not allow the temperature in the surrounding area of plants
to fall up to 0oC.
संबंधित प्रश्न
State three ways to minimize the global warming.
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A piece of ice is heated at a constant rate. The variation of temperature with heat input is shown in the graph below:
(i) What are represented by AB and CD?
(ii) What conclusion can you draw regarding the 110°c nature of ice from the above graph?
The temperature of a lead piece of mass 400 g rises from 20°C to 50°C when 1560 J of heat is supplied to it. Calculate: Heat capacity of lead piece.
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)
Two uniform brass rods A and B of length land 2l and radii 2r and r respectively are heated to the same temperature. The ratio of the increase in the volume ofB to that of A is ____________.
Two metals A and B have specific heat capacities in the ratio 2:3. If they are supplied same amount of heat then
Which metal piece will have greater mass if the rise in temperature is the same for both metals?
We would like to make a vessel whose volume does not change with temperature (take a hint from the problem above). We can use brass and iron `(β_(vbrass) = (6 xx 10^(–5))/K and β_(viron) = (3.55 xx 10^(–5))/K)` to create a volume of 100 cc. How do you think you can achieve this.
