Advertisements
Advertisements
प्रश्न
Give reasons for the following:
Even when the water in the lakes is frozen, fish can survive.
Advertisements
उत्तर
Even when the water in the lakes is frozen, fishes can survive due to anomalous expansion of water, water has maximum density at 4°C and this dense water remains at the bottom of the lake and the upper layer of water is less dense and freezes but the temperature of each layer of water below increases by 1°C. Thus it is warmer in the lakes below the ice layer. This helps the fishes to survive.C and this dense water remains at the bottom of the lake and the upper layer of water is less dense and freezes but the temperature of each layer of water below increases by 1°C. Thus it is warmer in the lakes below the ice layer. This helps the fishes to survive.
APPEARS IN
संबंधित प्रश्न
A 50 kg man is running at a speed of 18 km h−1. If all the kinetic energy of the man can be used to increase the temperature of water from 20°C to 30°C, how much water can be heated with this energy?
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.
At what temperature is the density of water is maximum? State its value.
Water is cooled from 4 °C to 0 °C. It will :
Why does a thick glass tumbler crack when very hot water is poured in it?
The following diagrams illustrate three situations involving thermometers which are labeled A, Band C. In each situation the thermometers indicate different readings.
(i) What do you expect the approximate reading of the thermometer B and C would be? Give a reason for your answer.
(ii) How would the readings of A and B help you in calibrating a thermometer?
Observe the following diagram and write the answers to the questions given below.
- Which process does the graph represent?
- What is the range of temperature responsible for the behaviour?
Name the following diagram appropriately.
A graph between the volume and temperature of water is shown. Explain the anomalous behaviour of water.
