26145.An ideal gas exert a pressure P. the mean kinetic energy per unit volume is E. which of the following relations is correct –
P = E
P = E/2
P = 2E/3
P = 3E/2
26146.The difference between the principal specific heats of nitrogen is 300 J/kg K and ratio of the two specific heats is 1.4. Then the CP is
1050 J/kg K
650 J/kg K
750 J/kg K
150 J/kg K
26147.PV/3 = RT, V represents volume of
Any amount of gas
2 moles of gas
3 moles of gas
4 moles of gas
26148.Energy supplied to convert unit mass of substance from solid to liquid state at its melting point is called
Latent heat of fusion
Evaporation
Solidification
Latent heat of fission
26149.If 2 kcal, of heat is supplied to a system cause to change the internal energy of a gas is 5030 J, and external work done is 3350 J, then what is mechanical equivalent of heat?
41.90 J/kcal
4190 J/cal
4.19 J/kcal
4.19 J/cal
26150.The average kinetic energy of the molecules of a gas at 27°C is 9 × 10–20 J. what is its average K.E. at 227°C?
5 × 10–20 J
10 × 10–20 J
15 × 10–20 J
20 × 10–20 J
26151.Mean square velocity of five molecules of velocities 2 m/s, 3 m/s, 4 m/s, 5 m/s and 6 m/s is
10 m2/s2
18 m2/s2
20 m2/s2
15 m2/s2
26152.For a gas, the r.m.s. speed at 800K is
Half the value at 200 K
Double the value at 200 K
Same as at 200 K
Four times the value at 200 K
26153.The internal energy of one mole of an ideal gas depend upon
Volume of gas
Temperature of gas
Nature of gas
Density of gas
26154.The root mean square speed of hydrogen molecules at 300K is 1930 m/s. then the root mean square speed of oxygen molecule at 900K will be
1930$\sqrt{3}$ m/s
838 m/s
643 m/s
$\dfrac{1930}{\sqrt{3}}$ m/s
26155.If at same temperature and pressure, the densities for two diatomic gases are respectively d1 and d2, then the ratio of velocities of sound in these will be
$\sqrt{\dfrac{\text{d}_2}{\text{d}_1}}$
$\sqrt{\dfrac{\text{d}_1}{\text{d}_2}}$
d1d2
$\sqrt{\text{d}_1\text{d}_2}$
26156.5 gm of air is heated from 273 K to 275 K. the change in internal energy of air will be
(CV = 172 cal/kg K and 4.2 J/cal)
(CV = 172 cal/kg K and 4.2 J/cal)
7.22 J
5.22 J
8.16 J
3.5 J
26157.K.E. per unit volume is given by
E = $\dfrac{3}{2}$p
E = $\dfrac{2}{3}$p
E = $\dfrac{3}{2}$mv2
None of these
26158.Mean kinetic energy per gram molecule of a gas is given by
$\dfrac{3}{2}RT$
kT
$\dfrac{1}{2}kT$
$\dfrac{3}{2}kT$
26159.If E is the kinetic energy per mole of a gas, and T is the absolute temperature, then the universal gas constant is given by
$R = \dfrac{\text{3T}}{\text{2E}}$
$R = \dfrac{\text{2E}}{\text{3T}}$
$R = \dfrac{\text{3E}}{\text{2T}}$
$R = \dfrac{\text{2T}}{\text{3E}}$
26160.According to kinetic theory of gasses at absolute zero temperature
Water freezes
Liquid helium freezes
Molecules motion stops
Liquid hydrogen freezes
26161.The mean translational K.E. per unit volume E and the pressure P of a perfect gas are related as
P = $\dfrac{E}{2V}$
P = $\dfrac{2E}{3V}$
P = $\dfrac{3}{2}EV$
P = $\dfrac{3E}{2V}$
26162.One mole of ideal gas required 207 J heat to rise the temperature by 10 K when heated at constant pressure. If the same gas is heated at constant volume to raise the temperature by the same 10K the heat required is (R = 8/3 J/mole K)
1987 J
29 J
215.3 J
124 J
26163.The root mean square speed of hydrogen molecules at 300 K is 1930 m/s. then the root mean square speed of oxygen molecules at 900 K will be
1930$\sqrt{3}$ m/s
836 m/s
643 m/s
$\dfrac{1930}{\sqrt{3}}$ m/s
26164.If 1 kg of water at its normal boiling point forms 1.671 m3 of steam, the external latent heat of vaporization of water is about (J = 4200 J/kcal)
400 kcal/kg
40 kcal/kg
4 kcal/kg
40 cal/kg