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प्रश्न
How do fishes survive in frozen lakes?
उत्तर
Fishes survive in pond even when the atmospheric temperature is below 0°C. It is because of anomalous expansion of water. When the temperature falls below 0°C water changes into ice and rises to the top and ice being poor conductor of heat helps to keep water below it at 4°C and fish can live in pond water.
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संबंधित प्रश्न
Give reason of Water pipes burst in severe winter.
1 kg of ice at 0°C is mixed with 1 kg of steam at 100°C. What will be the composition of the system when thermal equilibrium is reached? Latent heat of fusion of ice = 3.36 × 103 J kg−1 and latent heat of vaporization of water = 2.26 × 106 J kg−1.
On a winter day the temperature of the tap water is 20°C whereas the room temperature is 5°C. Water is stored in a tank of capacity 0.5 m3 for household use. If it were possible to use the heat liberated by the water to lift a 10 kg mass vertically, how high can it be lifted as the water comes to the room temperature? Take g = 10 m s−2.
Consider the situation of the previous problem. Assume that the temperature of the water at the bottom of the lake remains constant at 4°C as the ice forms on the surface (the heat required to maintain the temperature of the bottom layer may come from the bed of the lake). The depth of the lake is 1.0 m. Show that the thickness of the ice formed attains a steady state maximum value. Find this value. The thermal conductivity of water = 0.50 W m−1°C−1. Take other relevant data from the previous problem.
Explain the following
A glass bottle completely filled with water and tightly closed at room temperature is likely to burst when kept in the freezer of a refrigerator.
Draw a graph between volume and temperature, when 5 cm3 of ice at -10°C is heated to form water at +10°C.
Explain, why are the exposed water pipes lagged with straw during severe winter?
In a region with a cold climate the aquatic animals can survive at 4 °C, because _______.
Write a short note.
Anomalous behaviour of water
A graph between the volume and temperature of water is shown. Explain the anomalous behaviour of water.
