SCERT Maharashtra solutions for Physics [English] 12 Standard HSC chapter 3 - Kinetic Theory of gases and Radiation [Latest edition]

The average energy per molecule is proportional to ______ 

The number of degrees of freedom, for the vibrational motion of a polyatomic molecule, depends on the ______ 

The power radiated by a perfect blackbody depends only on its ______ 

If the absolute temperature of a body is doubled, the power radiated will increase by a factor of ______ 

Calculate the value of λ_max for radiation from a body having a surface temperature of 3000 K. (b = 2.897 x 10-3 m K) 

The molar specific heat of a gas at constant volume is 12307.69 J kg^-1 K^-1. If the ratio of the two specific heats is 1.65, calculate the difference between the two molar specific heats of gas. 

Calculate the energy radiated in one minute by a blackbody of surface area 200 cm² at 127 °C (σ = 5.7 x 10^-8 J m^-2 s^-1 K^-4)  

Under which condition laws of Boyle, Charles, and Gay-Lussac are valid?

On what, the values of absorption coefficient, reflection coefficient, and transmission coefficient depend, in addition to the material of the object on which the radiation is an incident? 

Why the temperature of all bodies remains constant at room temperature?

Above what temperature, all bodies radiate electromagnetic radiation? 

If the density of nitrogen is 1.25 kg/m³ at a pressure of 10⁵ Pa, find the root mean square velocity of nitrogen molecules. 

Find the kinetic energy of 3 litre of gas at S.T.P given standard pressure is 1.013 × 10⁵ N/m². 

Determine the pressure of nitrogen at 0°C if the density of nitrogen at N.T.P. is 1.25 kg/m³ and R.M.S. speed of the molecules at N.T.P. is 489 m/s.  

State factors on which the amount of heat radiated by a body depends.

Show that for monoatomic gas the ratio of the two specific heats is 5:3. 

Show that for diatomic gas the ratio of the two specific heats is 7:5.

Show the graphical representation of radiant power of a black body per unit range of wavelength as a function of wavelength.

Draw a neat labeled diagram of Ferry’s black body. 

Compare the rate of radiation of metal bodies at 727 °C and 227 °C.  

1000 calories of radiant heat are incident on a body. If the body absorbs 400 calories of heat, find the coefficient of emission of the body. 

A metal cube of length 4 cm radiates heat at the rate of 10 J/s. Find its emissive power at a given temperature. 

Show that the root means the square speed of the molecules of a gas is directly proportional to the square root of the absolute temperature of the gas.  

Show that the average energy of the molecules of a gas is directly proportional to the absolute temperature of the gas. 

Calculate the ratio of two specific heats of polyatomic gas molecules.  

Explain the construction and working of Ferry’s black body.

Compare the rates of emission of heat by a blackbody maintained at 627°C and at 127°C, if the black bodies are surrounded by an enclosure at 27°C. What would be the ratio of their rates of loss of heat? 

Determine the molecular kinetic energy (i) per mole (ii) per gram (iii) per molecule of nitrogen molecules at 227°C, R = 8.310 J mole^-1 K^-1,No = 6.03 x 10²⁶ moleculesKmole^-1. Molecular weight of nitrogen = 28. 

The velocity of the three molecules is 2 km s^-1, 4 km s^-1, 6 km s^-1. Find (i) mean square velocity (ii) root mean square velocity. 

Explain the spectral distribution of blackbody radiation.

Derive the expression for the average pressure of an ideal gas.

Derive Mayer’s relation.