The temperature of the atmosphere at a high altitude is around `500^(@)C`. Yet an animal there would freeze to death and not boil. Explain.

It has been recorded that the temperature of the earth's atmosphere has in creased by 0.6^(@)C . a. What has caused this increase ? b. Explain its consquences.

On a cold winter day, the atmospheric temperature is -theta (on celsius scale) which is below 0^(@)C . A cylindrical drum of height h made of a bad conductor is completely filled with water at 0^(@)C and is kept outside without any lid. Calculate the time taken for the whole mass of water to freeze. Thermal conductivity of ice is K and its latent heat of fusion is L . Neglect expansion of water on freezing.

a. The top of the atmosphere is at about 400 kV with respectto the surface of the earth, corresponding to an electric field that decreases with altitude. Near the surface of the earth, the field is about 100 Vm^(-1). Why then do we not get a electric shock as we step out of our house into the openy (Assume the house to be a steel cage so there is no field inside!) b. A man fixes outside his house one evening a two metre high insulating slab carrying on its top a large aluminium sheet of area 1m^(2) . Will he get an electric shock if he touches the metal sheet next morning? c. The discharging current in the atmosphere due to the small conductivity of air is known to be 1800A on an average over the globe. Why then does the atmosphere not discharge itself completely in due course and become electrically neutral? In other words, what keeps the atmosphere charged? d. What are the forms of energy into which the electrical energy of the atmosphere is dissipated during a lightning? (Hint: The earth has an electric field of about 100 Vm^(-1) at its surface in the downward direction, corresponding to a surface charge density =-10^(-9) Cm^(-2) ?.

In the planet Mars the average temperature is around -53^(@)C and atmospheric pressure is 0.7 kPa. Calculate the number of moles of the molecules inunit volume in the planet Mars.

In the planet Mars, the average temperature is around -53^(@)C and atmospheric pressure is 0.9 kPa. Calculate the number of moles of the molecules in unit volume in the planet Mars? Is this greater than that in earth ?

A man starts bicycling in the morning at a temperature around 25^(@)C he checked the pressure of tire which is equal to be 500 Kpa. Afternoon he found that the absolute pressure in the tyre is increased to 520 Kpa. By assuming the expansion of tyre is negligible what is the temperature of type at afternoon ?

In a constant volume gas thermometer, the pressure of the working gas is measured by the difference in the levels of mercury in the two arms of a U-tube connected to the gas at one end. When the bulb is placed at the room temperature 27.0^0 C , the mercury column in the arm open to atmosphere stands 5.00 cm above the level of mercury in the other arm. When the bulb is placed in a hot liquid, the difference of mercury levels becomes 45.0 cm . Calculate the temperature of the liquid. (Atmospheric pressure = 75.0cm of mercury).