Advertisements
Advertisements
प्रश्न
The average translational kinetic energy of air molecules is 0.040 eV (1 eV = 1.6 × 10−19J). Calculate the temperature of the air. Boltzmann constant k = 1.38 × 10−23 J K−1.
Advertisements
उत्तर
We know from kinetic theory of gases that the average translational energy per molecule is \[\frac{3}{2}kT\].
Now,
Eavg= 0.040 eV = \[0.040 \times 1 . 6 \times {10}^{- 19} = 6 . 4 \times {10}^{- 21} J\]
\[6 . 40 \times {10}^{- 21} = \frac{3}{2} \times 1 . 38 \times {10}^{- 23} \times T\]
\[ \Rightarrow T = \frac{2}{3} \times \frac{6 . 40 \times {10}^{- 21}}{1 . 38 \times {10}^{- 23}} = 309 . 2 \text { K }\]
APPEARS IN
संबंधित प्रश्न
Comment on the following statement: the temperature of all the molecules in a sample of a gas is the same.
When you come out of a river after a dip, you feel cold. Explain.
The mean speed of the molecules of a hydrogen sample equals the mean speed of the molecules of a helium sample. Calculate the ratio of the temperature of the hydrogen sample to the temperature of the helium sample.
Use R = 8.314 JK-1 mol-1
During an experiment, an ideal gas is found to obey an additional law pV2 = constant. The gas is initially at a temperature T and volume V. Find the temperature when it expands to a volume 2V.
Use R = 8.3 J K-1 mol-1
Figure shows a cylindrical tube of cross-sectional area A fitted with two frictionless pistons. The pistons are connected to each other by a metallic wire. Initially, the temperature of the gas is T0 and its pressure is p0 which equals the atmospheric pressure. (a) What is the tension in the wire? (b) What will be the tension if the temperature is increased to 2T0 ?
An adiabatic cylindrical tube of cross-sectional area 1 cm2 is closed at one end and fitted with a piston at the other end. The tube contains 0.03 g of an ideal gas. At 1 atm pressure and at the temperature of the surrounding, the length of the gas column is 40 cm. The piston is suddenly pulled out to double the length of the column. The pressure of the gas falls to 0.355 atm. Find the speed of sound in the gas at atmospheric temperature.
Answer in brief:
A gas in a cylinder is at pressure P. If the masses of all the molecules are made one-third of their original value and their speeds are doubled, then find the resultant pressure.
At what temperature will oxygen molecules have same rms speed as helium molecules at S.T.P.? (Molecular masses of oxygen and helium are 32 and 4 respectively).
When a gas is heated, its temperature increases. Explain this phenomenon on the basis of the kinetic theory of gases.
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)
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?
The average translational kinetic energy of gas molecules depends on ____________.
The graph of kinetic energy against the frequency v of incident light is as shown in the figure. The slope of the graph and intercept on X-axis respectively are ______.
When photons of energy hv fall on a metal plate of work function 'W0', photoelectrons of maximum kinetic energy 'K' are ejected. If the frequency of the radiation is doubled, the maximum kinetic energy of the ejected photoelectrons will be ______.
Average kinetic energy of H2 molecule at 300K is 'E'. At the same temperature, average kinetic energy of O2 molecule will be ______.
23Ne decays to 23Na by negative beta emission. Mass of 23Ne is 22.994465 amu mass of 23Na is 22.989768 amu. The maximum kinetic energy of emitted electrons neglecting the kinetic energy of recoiling product nucleus is ______ MeV.
If a = 0. 72 and t = 0.04, then the value of r is ______.
Which of the following materials is diathermanous?
