Advertisements
Advertisements
प्रश्न
Why do the farmers fill their fields with water on a cold winter night?
Advertisements
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
Water is used in hot water bottles for fomentation. Give a reason.
The S.I. unit of specific heat capacity is ______.
Explain the term boiling point ?
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.
Define heat capacity.
Why is specific heat capacity taken as a measure of thermal inertia?
Explain, why do sandy soils, get heated up quickly as compared to wet soils?
The cold object the hot object enclosed in one box of heat-resistant material.
- What changes will occur in the two objects when temperature flows from those objects?
- Which principle can show that the energy exchange takes place between two objects only when kept in isolated system?
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")`
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.
