Physics-
General
Easy
Question
Consider a spherical shell of radius R at temperature T. The black body radiation in side it can be considered as an ideal gas of photons with internal energy per unit volume u=
and pressure 
If the shell now undergoes an adiabatic expansion the relation between T and R is:
The correct answer is:
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then exhaustive range of 
is
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Assertion : Bohr had to postulate that the electrons in stationary orbits around the nucleus do not radiate.
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The centre of the Sun consists of gases whose average molecular weight is 2. If the density of the gases is 
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Chemistry-General
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What is the numerical value of gas constant R, in lit 
?
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Chemistry-General
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At 0°C and a pressure of 2 atmospheres volume of 1 gram of a diatomic gaseous element is 350ml. Weight of 1 atom of the element in grams is
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Oxygen is present in a flask of 1.12L capacity at a pressure of 
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Chemistry-General
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The average speed at 
K and most probable speed at 
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The RMS velocity of a gas is 
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A student forgot to add the reaction mixture to the round bottomed flask at 27°C but instead he/she placed the flask on the flame. After a lapse of time, he realized his mistake and using a pyrometer he found the temperature of flask was 477°C. The fraction of air that has been expelled out is
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On a ship sailing in pacific ocean where temperature is 23.4°C, a balloon is filled with 2 L air. The volume of the balloon when the ship reaches Indian ocean at a temperature of 26.1°C is
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3.5 gms of carbon monoxide at 0°C and 760mm pressure contains _______ molecules. [Avogadro number = 
]
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Chemistry-General
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Chemistry-General
